High Levels of Kinesiophobia at Discharge from the Hospital May Negatively Affect the Short-Term Functional Outcome of Patients Who Have Undergone Knee Replacement Surgery.

BACKGROUND: Kinesiophobia is a psycho-cognitive factor that hampers recovery after orthopedic surgery. No evidence exists on the influence of kinesiophobia on the short-term recovery of function in patients with knee replacement (KR). Therefore, the aim of the present study is to investigate the impact of kinesiophobia on short-term patient-reported outcomes (PROMs) and performance-based measures (PBMs). METHODS: Forty-three KR patients filled in the Tampa scale for kinesiophobia (TSK) at time of discharge. Patients with TSK ≥ 37 were allocated to the kinesiophobia group (n = 24), others to the no-kinesiophobia group (n = 19). Patients were asked to complete PROMs and to execute PBMs at discharge and at 6-weeks follow-up. An independent samples t-test was used to compare group differences for PROMs and PBMs at both measurement sessions. Multiple linear regression analysis models were used to model PBM outcomes from age, pain and TSK scores. RESULTS: Significant differences were observed between groups for PROMs and PBMs. Kinesiophobia significantly contributed to the reduced functional outcomes. CONCLUSION: At discharge from the hospital, 55.8% of KR patients demonstrated high levels of kinesiophobia (TSK ≥ 37). This may negatively influence short-term recovery of these patients, by putting them at higher risk for falling and reduced functionality.

Lower extremity gait kinematics outcomes after knee replacement demonstrate arthroplasty-specific differences between unicondylar and total knee arthroplasty: A pilot study.

BACKGROUND: The aim of the present study is to compare sagittal gait kinematics of ankle, knee and hip joints between subjects with unicondylar and total knee arthroplasty and age matched healthy controls. Since unicondylar knee replacement is a less invasive procedure, which more closely preserves knee joint anatomy, we hypothesized that one year post unicondylar knee arthroplasty patients would demonstrate more normal gait patterns than patients with total knee arthroplasty. RESEARCH QUESTION: Do unicondylar and total knee arthroplasty patients display similar gait kinematics one year after surgery? METHODS: Fourteen subjects (8 posterior stabilized and 6 medial unicondylar knee replacements) that were one year post surgery, and 6 healthy control subjects underwent a 3D gait analysis and a physical examination (range of motion, muscle strength). Statistical parametric mapping was used to compare gait kinematics of the lower limbs between groups. Additionally, differences in peak angles and clinical outcomes were assessed using a one-way ANOVA between subjects analysis. RESULTS: Both knee replacement groups showed reduced knee flexion range of motion and reduced muscle strength at the operated leg compared to the control group. Subjects with TKA demonstrated reduced knee flexion at loading response and midstance of the gait cycle. Both UKA and TKA demonstrated significantly less knee flexion during swing. SIGNIFICANCE: The results of this study demonstrate arthroplasty-specific differences in muscle strength, range of motion and gait kinematics of the lower limb one year after knee surgery. Future planning of post-surgery follow-up should addresses these arthroplasty-specific weaknesses and gait deviations.

Hip and knee kinematics of the forward lunge one year after unicondylar and total knee arthroplasty.

Patients with unicondylar knee arthroplasty (UKA) report higher functionality compared to those with total knee arthroplasty (TKA). However, these patients should also be assessed during more demanding tasks in order to appreciate their true functionality. The forward lunge (FL) is a motor task commonly used in clinics to evaluate functional recovery after knee replacement surgery. Unfortunately, clear evidence comparing FL kinematics between patients with UKA and TKA is still missing. The purpose of this study was to compare hip and knee joint kinematics during the FL between patients with UKA, TKA and controls. Twenty subjects (8 TKA, 6 UKA, 6 controls) underwent 3D motion analysis during a FL. Differences in hip and knee kinematics between groups were identified using statistical parametric mapping. We concluded that patients with TKA demonstrated reduced knee and hip flexion angles during the loaded phase of the FL, which could have been an attempt to unload the knee joint. This is in contrast to patients with UKA, who showed similar knee and hip joint kinematics compared to controls throughout the entire FL. It seems that retaining the cruciate ligaments is beneficial for the execution of a complex motor task such as the FL.

The implementation of inertial sensors for the assessment of temporal parameters of gait in the knee arthroplasty population.

BACKGROUND: The use of inertial measurement units for the evaluation of temporal parameters of gait has been studied in many populations. However, currently no studies support the use of inertial measurement units for this purpose in the knee arthroplasty population. The objective of the present study was to investigate the agreement between an inertial measurement and camera based system for the assessment of temporal gait parameters in a knee arthroplasty population. METHODS: Sixteen knee arthroplasty patients performed 3 gait trials at a self-selected speed along a 6 m walk-way. During the gait trials, gyroscope data from shank-worn inertial measurement units and motion data from optoelectronic cameras were collected simultaneously. A custom-made peak detection algorithm was used to identify gait events from gyroscope data, in order to compute cycle time, stance time and swing time. A marker and coordinate based algorithm was used to calculate temporal gait parameters from kinematical data derived from the camera system. Temporal variables were compared between both methods by calculating intra-class correlation coefficients, mean errors and root mean squared errors. Furthermore, Bland-Altman plots were constructed to assess the agreement between both methods. FINDINGS: Overall good to excellent intra-class correlation values (0.826-0.972) were found. Root mean square errors between both methods ranged from 0.036 to 0.055 s. High levels of agreement were observed for all variables. INTERPRETATION: These findings suggest that inertial measurement units can be used for outside laboratory assessment (e.g. in a hospital environment) of temporal gait parameters in the knee arthroplasty population.

A New Prediction Model for Patient Satisfaction After Total Knee Arthroplasty.

BACKGROUND: Total knee arthroplasty (TKA) is a proven and cost-effective treatment for osteoarthritis. Despite the good to excellent long-term results, some patients remain dissatisfied. Our study aimed at establishing a predictive model to aid patient selection and decision-making in TKA. METHODS: Using data from our prospective arthroplasty outcome database, 113 patients were included. Preoperatively and postoperatively, the patients completed 107 questions in 5 questionnaires: Knee Injury and Osteoarthritis Outcome Score, Oxford Knee Score, Pain Catastrophizing Scale, Euroqol questionnaire, and Knee Scoring System. First, outcome parameters were compared between the satisfied and dissatisfied group. Second, we developed a new prediction tool using regression analysis. Each outcome score was analyzed with simple regression. Subsequently, the predictive weight of individual questions was evaluated applying multiple linear regression. Finally, 10 questions were retained to construct a new prediction tool. RESULTS: Overall satisfaction rate in this study was found to be 88%. We identified a significant difference between the satisfied and dissatisfied group when looking at the preoperative questionnaires. Dissatisfied patients had more preoperative symptoms (such as stiffness), less pain, and a lower quality of life. They were more likely to ruminate and had a lower preoperative Knee Scoring System satisfaction score. The developed prediction tool consists of 10 simple but robust questions. Sensitivity was 97% with a positive-predictive value of 93%. CONCLUSIONS: Based upon preoperative parameters, we were able to partially predict satisfaction and dissatisfaction after TKA. After further validation, this new prediction tool for patient satisfaction following TKA may allow surgeons and patients to evaluate the risks and benefits of surgery on an individual basis and help in patient selection.

Stabilization of proximal interphalangeal joint in lesser toe deformities with an angulated intramedullary implant.

BACKGROUND: Hammertoe and claw toe are among the most common foot deformities. Proximal interphalangeal (PIP) joint realignment can be performed using specifically designed intramedullary implants. The aim of this study was to assess the clinical outcome of patients with lesser toes deformities undergoing PIP joint realignment using an intramedullary implant. METHODS: Patients requiring PIP joint realignment were included in this prospective multicenter observational study and followed for 12 months. A total of 156 toes, in 117 patients were implanted with the implants. Complications and radiological and functional outcome were assessed. RESULTS: The proportion of joints fused on X-rays was 83.8% (95% CI: 77.8, 89.7) after 1 year. American Orthopaedic Foot and Ankle Society lesser metatarsophalangeal-interphalangeal scale (AOFAS-LMIS) improved from 40.4 (SD = 18.3) preoperatively to 85.5 (SD = 9.2) after 1 year. The proportion of patients with pain was 15.5% after 6 weeks and decreased to 4.7% after 1 year. Of the patients, 98% were satisfied about the operation. In patients with incomplete fusion of the PIP joint after 1 year, AOFAS-LMIS improved from 36.7 (SD = 18.9) preoperatively to 84.2 (SD = 10.1) 1 year postoperatively, while pain was reported by 2 patients (8.3%) after 1 year. Toe malalignment and lack of toe pulp-contact were reported slightly more frequently than for the whole group of patients, but not for the majority of the cases. Overall, complications were reported intraoperatively in 1.3% of the patients (2 cases) and postoperatively in 3.2% (5 cases). Revision was required in 1 case. Mallet toe deformity was found in 2.0% of the patients after 1 year. CONCLUSION: This study showed that the use of an intramedullary implant for PIP realignment led to a high rate of fusion and a good outcome. No need of reoperation was reported for patients with incomplete joint fusion who had a stable joint with no pain. LEVEL OF EVIDENCE: Level IV, prospective case series.

Total knee arthroplasty at 15-17 years: does implant design affect outcome?

PURPOSE: A study was conducted to compare minimum 15-year survivorship and outcome of the Genesis I and II implants for total knee arthroplasty (TKA). METHODS: We retrospectively reviewed 245 consecutive TKA implanted between January 1995 and October 1997. Genesis I was implanted in 156 knees and Genesis II in 89 knees. RESULTS: At 15-17 years, 75 patients (31%) had died, 28 patients (11%) were lost to follow-up and 11 TKA were revised (4.6%), including ten Genesis I (6.4%) and one Genesis II (1.1%); 131 TKA (53%) were available for follow-up. Cumulative survivorship was 92.4% at 15.7 years. Survival in patients <69 years at surgery was lower (88.0%) compared with patients ≥69 years (98.5%; p = 0.023). In patients <69 years, Genesis I survival (84.3%) was worse compared with Genesis II (97.1%) (p = 0.018). Polyethylene (PE) Insert thickness ≤11 mm had significantly better survivorship (97.1%) compared with PE >11 mm (56.7%) (p < 0.0001) CONCLUSIONS: At a minimum of 15 years, the overall (92.4%) survivorship of Genesis TKA was good, with excellent (98.1%) survivorship of the Genesis II design. Revision rates were higher with Genesis I in the younger age group and with insert thickness >11 mm, possibly due to longer shelf life of less frequently used sizes.

Pulsed electromagnetic fields after arthroscopic treatment for osteochondral defects of the talus: double-blind randomized controlled multicenter trial.

BACKGROUND: Osteochondral talar defects usually affect athletic patients. The primary surgical treatment consists of arthroscopic debridement and microfracturing. Although this is mostly successful, early sport resumption is difficult to achieve, and it can take up to one year to obtain clinical improvement. Pulsed electromagnetic fields (PEMFs) may be effective for talar defects after arthroscopic treatment by promoting tissue healing, suppressing inflammation, and relieving pain. We hypothesize that PEMF-treatment compared to sham-treatment after arthroscopy will lead to earlier resumption of sports, and aim at 25% increase in patients that resume sports. METHODS/DESIGN: A prospective, double-blind, randomized, placebo-controlled trial (RCT) will be conducted in five centers throughout the Netherlands and Belgium. 68 patients will be randomized to either active PEMF-treatment or sham-treatment for 60 days, four hours daily. They will be followed-up for one year. The combined primary outcome measures are (a) the percentage of patients that resume and maintain sports, and (b) the time to resumption of sports, defined by the Ankle Activity Score. Secondary outcome measures include resumption of work, subjective and objective scoring systems (American Orthopaedic Foot and Ankle Society--Ankle-Hindfoot Scale, Foot Ankle Outcome Score, Numeric Rating Scales of pain and satisfaction, EuroQol-5D), and computed tomography. Time to resumption of sports will be analyzed using Kaplan-Meier curves and log-rank tests. DISCUSSION: This trial will provide level-1 evidence on the effectiveness of PEMFs in the management of osteochondral ankle lesions after arthroscopy. TRIAL REGISTRATION: Netherlands Trial Register (NTR1636).

Soft tissue balance in total knee arthroplasty: does stress relaxation occur perioperatively?

The restoration of correct soft tissue tension is key to achieving a successful total knee arthroplasty. However, it remains unclear whether the status achieved immediately after the operation will persist over time. Some surgeons believe soft tissue stress relaxation occurs and therefore the knee loosens somewhat after the procedure. It was the aim of this study to investigate this hypothesis. We analyzed 25 in vivo total knee implantations using contemporary computer navigation technology to assess and quantify perioperative soft tissue relaxation. Mediolateral joint laxity and maximal passive extension were analyzed immediately intraoperatively and 30 minutes later under the same conditions. Stress relaxation occurred in all cases, leading to increased mediolateral laxity by an average of 1 mm on the medial and lateral sides. Maximal passive extension increased by an average of 3 degrees. This data confirms the hypothesis the knee becomes looser in the early phase after total knee arthroplasty.