Total knee arthroplasty (TKA) aims to alleviate pain and restore joint biomechanics to an equivalent degree to age-matched peers. Zimmer Biomet's Nexgen TKA was the most common implant in the UK between 2003 and 2016. This study compared the biomechanical outcomes of the Nexgen implant against a cohort of healthy older adults to determine whether knee biomechanics is restored post-TKA. Patients with a primary Nexgen TKA and healthy adults >55 years old with no musculoskeletal deficits or diagnosis of arthritis were recruited locally. Eligible participants attended one research appointment. Bilateral knee range of motion (RoM) was assessed with a goniometer. A motorised arthrometer (GENOUROB) was then used to quantify the anterior-posterior laxity of each knee. Finally, gait patterns were analysed on a treadmill. An 8-camera Vicon motion capture system generated the biomechanical model. Preliminary statistical analyses were performed in SPSS (α = 0.05; required sample size for ongoing study: n=21 per group). The patient cohort (n=21) was older and had a greater BMI than the comparative group (n=13). Patients also had significantly poorer RoM than healthy older adults. However, there were no inter-group differences in knee laxity, walking speed or cadence. Gait kinematics were comparable in the sagittal plane during stance phase. Peak knee flexion during swing phase was lower in the patient group, however (49.0° vs 41.1°). Preliminary results suggest that knee laxity and some spatiotemporal and kinematic parameters of gait are restored in Nexgen TKA patients. While knee RoM remains significantly poorer in the patient cohort, an average RoM of >110° was achieved. This suggests the implant provides sufficient RoM for most activities of daily living. Further improvements to knee kinematics may necessitate additional rehabilitation. Future recruitment drives will concentrate on adults over the age of 70 for improved inter-group comparability

Total Knee Arthroplasty (TKA) improves the quality of life of osteoarthritic and rheumatoid arthritis patients, however, is associated with moderate to severe postoperative pain. There are multiple methods of managing postoperative pain that include epidural anesthesia but it prevents early mobilization and results in postoperative hypotension and spinal infection. Controlling local pain pathways through intra-articular administration of analgesics is a novel method and is inexpensive and simple. Hence, we assess the effects of postoperative epidural bupivacaine injection along with intra-articular injection in total knee replacement patients. The methodology included 100 patients undergoing TKA randomly divided into two groups, one administered with only epidural bupivacaine injection and the other with intra-articular cocktail injection. The results were measured based on a 10-point pain assessment scale, knee's range of motion (ROM), and Lysholm knee score. The VAS score was lower in the intra-articular cocktail group compared to the bupivacaine injection group until the end of 1-week post-administration (p<0.01). Among inter-group comparisons, we observed that the range of motion was significantly more in cocktail injection as compared to the bupivacaine group till the end of one week (p<0.05). Lysholm's score was significantly more in cocktail injection as compared to the bupivacaine group till the end of one week (p<0.05). Our study showed that both epidural bupivacaine injection and intra-articular injection were effective in reducing pain after TKA and have a comparable functional outcome at the end of 4 weeks follow up. However, the pain relief was faster in cases with intra-articular injection, providing the opportunity for early rehabilitation. Thus, we recommend the use of intra-articular cocktail injection for postoperative management of pain after total knee arthroplasty, which enables early rehabilitation and faster functional recovery of these patients

3D measurement of joint angles so far has only been possible using marker-based movement analysis, and therefore has not been applied in (larger scale) clinical practice (performance test) and even less so in the free field (activity monitoring). 3D joint angles could provide useful additional information in assessing the risk of anterior cruciate ligament injury using a vertical drop jump or in assessing knee range of motion after total knee arthroplasty. We developed a tool to measure dynamic 3D joint angles using 6 inertial sensors, attached to left and right shank, thigh and pelvis. The same sensors have been used for activity identification in a previous study. To validate the setup in a pilot study, we measured 3D knee and hip angles using the sensors and a Vicon movement lab simultaneously in 3 subjects. Subjects performed drop jumps, squats and ran on the spot. The mean error between Vicon and sensor measurement for the maximum joint angles was 3, 7 and 8 degrees for knee flexion, ad/abduction and rotation respectively, and 9, 7 and 10 degrees for hip flexion, ad/abduction and rotation respectively. No calibration movements were required. A major part of the inaccuracy was caused by soft tissue effects and can partly be resolved by improved sensor attachment. These pilot results show that it is feasible to measure 3D joint angles continuously using unobtrusive light-weight sensors. No movement lab is necessary and therefore the measurements can be done in a free field setting, e.g. at home or during training at a sport club. A more extensive validation study will be performed in the near future

Total knee arthroplasty (TKA) is becoming more prevalent as the average age of the general population increases and is generally considered to be a very effective and successful surgery. However, functional recovery post-surgery can often be less than optimal. Neuromuscular electrical stimulation (NMES) is a beneficial therapy proven to improve haemodynamics and muscle strength and may be of great benefit in improving functional recovery in the acute phase post-TKA. The objective of the study was to assess functional recovery in the period immediately following TKA and hospital discharge in response to a home-based NMES programme. Twenty-six TKA patients were randomized into a NMES stimulation or placebo-controlled group. All participants were given a research muscle stimulator to use at home post-discharge for 90 minutes per day over a period of 5 weeks. In the stimulation group, application of stimulation resulted in an electrically activated contraction of the soleus muscle. Patients in the placebo-controlled group received sensory stimulation only. Outcome measures were physical activity levels, joint range of motion and lower limb swelling, which were measured pre-surgery and on a weekly basis post-discharge up until the sixth post-surgical week. 90 minutes per day NMES stimulation significantly increased the Activity Time (P = 0.029 week 1 post-discharge) and the number of Stepping Bouts (P < 0.05 weeks 1 to 4 post-discharge) in the early post-discharge phase. While there was a trend towards a greater knee flexion with use of NMES, this did not reach statistical significance (P = 0.722). No effect of NMES was observed on swelling (P > 0.05 for all measures). Compliance to the NMES therapy was measured by an on-board SIM card in the NMES device, with a 95% and 94% time compliance rate for the stimulation and placebo-controlled groups respectively. The results of this study suggest that NMES may be very useful in improving functional recovery through increasing physical activity levels in the early post-TKA discharge phase. The results of this study warrant further investigation into the use of an optimized NMES protocol whereby improvements in knee range of motion and swelling may also be observed

Purpose. This study was to investigate the effect of posterior tibial slope (PTS) on the kinematics in the cruciate-retaining total knee arthroplasty (CR-TKA) using 2- to 3- dimensional registration technique. Material & Methods. A total of 75 knees in 58 patients were recruited and categorized into the following two groups according to PTS. Group A was categorized PTS under 7degrees (n = 33) and group B was categorized PTS over 7 degrees (n = 42). The average age of group A and group B at the time of fluoroscopic surveillance date was 73.5 ± 7.4 years and 74.3 ± 4.5 years, respectively and the average follow-up period from operation date to fluoroscopic surveillance date was 13.8 ± 9.3 months and 16.7 ± 8.6 months, respectively. In vivo kinematics during sequential deep knee bending under weight-bearing condition were evaluated using fluoroscopic image analysis and 2- to 3- dimensional registration technique. Range of motion (ROM), axial rotation, anteroposterior (AP) translations of medial and lateral nearest points of the femoral component relative to the tibial component were measured and compared between the two groups. The nearest points were determined by calculating the closest distance between the surfaces of femoral component model and the axial plane of coordinate system of the tibial component. We defined external rotation and anterior translation as positive. P values under 0.05 was defined as statistically significant. Results. The mean PTS in group A and B were 5.5 ± 1.4°and 9.9 ± 1.9°, respectively. There was no statistically significant difference in the degrees of axial rotation from 0° to 110° of flexion between the two groups (4.9 ± 4.2° vs 5.2 ± 4.2°, p > 0.05), respectively. The hyperextension of group B were significantly larger than group A (−2.3 ± 6.6°vs −9.8 ± 8.7°, p <0.05). The ROM of group B were significantly larger than group A (118.7 ± 10.8°vs 128.7 ± 17.7°, p <0.05). However, there was no significant difference in the maximum flexion between the two groups (116.4 ±10.8°vs 118.9±14.5°, p >0.05), respectively. In terms of AP translation, medial nearest points were located significantly more posterior at 0°, 10°, 30°, 40° of flexion in group B compared to group A. There was no significant difference in the location of lateral nearest points between the two groups during all knee range of motion. Discussion/Conclusion. The results shown in this study demonstrated that the PTS influenced the kinematics and ROM under weight-bearing condition in CR-TKA. The large PTS induced great posterior displacement of medial nearest points during early flexion phase and increased hyperextension between the femoral and tibial components

Summary Statement. This work proved by prospective clinical and radiological controlled study that the best regimen for treatment of early KOA is combination of NSAIDS, physiotherapy, vasoprotective and vasodilator drugs, and alendronate. Introduction. There is controversy in the literatures regarding the best treatment for early knee osteoarthritis because there is a more controversy regarding the initiating factor of KOA The Objectives of this work were to evaluate the efficacy of various treatment regimens for the prevention of progression of early knee osteoarthritis (KOA). Also, to elucidate the factors for initiation and progression of KOA. Patients and Methods. Four groups of 50 patients with early KOA were treated with four treatment regimens. The first group (control) received analgesics as needed for one year. The second group received non steroidal anti-inflammatory drugs (NSAIDS) plus physiotherapy for one month; with analgesics as needed for the rest of the year. The third group received NSAIDS plus physiotherapy, plus vasoprotective and vasodilator drugs for one month; vasoprotective and vasodilator drugs for the next six months, and analgesics as needed for the rest of the year. The fourth group received NSAIDS plus physiotherapy, plus vasoprotective and vasodilator drugs plus alendronate for one month; vasoprotective and vasodilator drugs plus alendronate for the next six months; and analgesics as needed for the rest of the year. The age of the patients was from 40 to45years. There were 25 males and 25 females in each group. Patients with causes of secondary KOA (e.g. rheumatoid, gouty, traumatic, etc.) were excluded. All patients were subjected to Pre- and post treatment regimens clinical and radiological evaluation Clinical evaluation included history of progressive knee pain for 3–6weeks, limping, Visual analog pain score, tenderness, and knee range of motion. Radiological evaluation included 1.0 T MRI which was performed using proton density-weighted, fat-suppressed sequences. BML size and cartilage status were scored in the same sub regions according to the WORMS system. Results. Progression of KOA in the first, second, third, and fourth group were 66%, 55%, 25%, and 19% of patients respectively No sex difference was detected. Conclusion. The best treatment regimen for early KOA is combination of NSAIDS, physiotherapy, vasoprotective and vasodilator drugs, and alendronate. Vascular and local osteoporotic factors may play a major role in progression of KOA

Recent projections expect the number of revision knee replacements performed to grow from 38,000 in 2005 to 270,000 by the year 2030. 1. Although the results of primary total knee arthroplasty are well documented, with overall implant survivorship at 15 years greater than 95%. 2. the results of revision procedures are not as well known. What if the revision TKR fails and what is the prevalence of failure of revision TKRs, the complications and re-operation rates? There are various studies which has either exclusively dealt with the causes or outcomes of revision with a particular prosthesis and survivorship analysis. The effectiveness of revision total knee replacement must be considered in the light of complications rates which could be either medical, orthopaedic surgery related complications or combination of both. The purpose of this study was to evaluate the prevalence of complications, reoperation rates and outcomes in a single surgeon's series between 1984 and 2008. Ninety nine index revision cases were studied. Incidences of surgical complications were 52.5%. The total reoperation rate was 34.3% whilst single re revision accounted for 19.9% whereas multiple re-revision incidences were 4%. The mean outcome in terms of Knee Society Score, Knee Society Function, and Knee society range of motion was statistically and clinically significant between pre operative and posts operative score at one year and remained consistent with time. These results suggest that modern revision total knee replacement are satisfactory operations and the outcomes perhaps can be improved if relatively simple strategies are followed by focusing these operations to specialized that accumulate enough experience from these demanding surgeries. Overall the results asserts that even in the hands of an experienced surgeon the complications do occur which is usually multi factorial, whilst in the light of complications and reoperation incidence the patients can be counselled thoroughly before the procedure