We aim to determine the differences in lower limb joint
The objective of this study was to compare differences in alignment following robotic arm-assisted bi-unicompartmental knee arthroplasty (Bi-UKA) and conventional total knee arthroplasty (TKA). This was a prospective, randomised controlled trial of 70 patients. 39 TKAs were implanted manually, as per standard protocol at our institution, and 31 Bi-UKA patients simultaneously received fixed-bearing medial and lateral UKAs, implanted using robotic arm-assistance. Preoperative and 3-month postoperative CT scans were analysed to determine hip knee ankle angle (HKAA), medial distal femoral angle (MDFA), and medial proximal tibial angle (MPTA). Analysis was repeated for 10 patients by a second rater to validate measurement reliability by calculating the intra-class correlation coefficient (ICC). Mean change in HKAA towards neutral was 2.7° in TKA patients and 2.3° in Bi-UKA patients (P=0.6). Mean change in MDFA was 2.5° for TKA and 1.0° for Bi-UKA (P<0.01). Mean change in MPTA was 3.7° for TKA and 0.8° for Bi-UKA (P<0.01). Mean postoperative MDFA and MPTA for TKAs were 89.8° and 89.6° respectively, indicating orientation of femoral and tibial components perpendicular to the mechanical axis. Mean postoperative MDFA and MPTA for Bi-UKAs were 91.0° and 86.9° respectively, indicating a more oblique joint line orientation. Inter-rater agreement was excellent (ICC>0.99). Early functional activities, according to the new Knee Society Scoring System, favoured Bi-UKAs (P<0.05). Robotic arm-assisted, cruciate-sparing Bi-UKA better maintains the natural anatomy of the knee in the coronal plane and may therefore preserve normal joint
Purpose. to evaluate the
Summary. UC TKA showed similar anteroposterior translation and more femoral external rotation of earlier onset when compared to PS TKA. Introduction. Recently highly conforming ultracongruent TKA has been reintroduced with improved wear characteristics and lower complications. The purpose of the study was to assess
In this study we quantified and characterised
the return of functional mobility following open tibial fracture
using the Hamlyn Mobility Score. A total of 20 patients who had
undergone reconstruction following this fracture were reviewed at
three-month intervals for one year. An ear-worn movement sensor
was used to assess their mobility and gait. The Hamlyn Mobility
Score and its constituent
BACKGROUND. Many patients who underwent a THA, report a feeling of more “physiological” hip and of faster recovery when bigger heads are used. The aim of this study is to evaluate the walking recovery of patients after THA with different head diameters by the means of gait analysis. MATERIALS AND METHODS. A prospective, randomized, blind study was conducted on 60 patients operated by THA at our Institution. Inclusion criteria were: primary hip arthritis, women, age between 55 and 70 years. Exclusion criteria were: other problems influencing walking ability (previous operations of the lower limbs, spine disorders, knee or controlateral hip arthritis). The same uncemented stem, same uncemented press-fit cup, same surgical technique and approach (posterolateral), same surgeons, same postoperative protocol and rehabilitation were employed. The only difference was the head diameter. The patients were randomized into three groups, of twenty patients each one (28mm Cer-on-XPE, 36mm Cer-on-XPE, >42mm Met-on-Met). The gait evaluation have been performed at three temporal steps: preoperatively, two months postoperatively and four months postoperatively.
Introduction. While clinically successful for decades, CR TKA is persistently compromised by inconsistent PCL function. Problems of mid-flexion instability, incomplete knee flexion, erratic
It appears that double bundle anterior cruciate ligament reconstruction can reproduce the original anatomy of the ligament, restoring normal
Aim. The purpose of this study was to analyze the patellofemoral
Introduction. There has been renewed interest in the unicompartmental knee arthroplasty with reports of good long term outcomes. Advantages over a more extensive knee replacement include: preservation of bone stock, retention of both cruciate ligaments, preservation of other compartments and better knee
Introduction. The same cup orientation is classically applied to all cases of hip replacement (45° abduction, 20° anteversion). We hypothesize that this orientation must be adapted to the patient's hip range of motion. We tested this hypothesis by means of an experimental study with respect to hip range of motion, comparing the classical orientation (45° and 20°), and the orientation obtained with computer-assisted navigation. Material and Methods. The experimental model included a hemipelvis equipped with a femur whose mobility was controlled for three configurations: stiff (60°/0°, 15°/10°, 10°/10°), average (80°/10°, 35°/30°,35°/25°), mobile (130°/30°, 50°/50°, 45°/35°). The hemipelvis and the cup holder were equipped with an electromagnetic system (Fastrack ™) to measure cup orientation. The Pleos™ navigation system (equipping the hemipelvis, the femur, and the cup holder) guided the cup orientation by detecting the positions risking impingement through a
Introduction. Patellofemoral complications remain a very common post-operative problem in association with total knee arthoplasty (TKA). As malrotation of the femoral component is often considered crucial for the outcome, we analyzed absolute rotational femoral alignment in relation to patellar tracking pre- and postoperatively and matched the results with the two year functional outcome. Methods. Femoral rotation and component rotation was assessed by axial radiography using condylar twist angle (CTA). The lateral patellar displacement, patellar tilt and Insall-Salvati index were measured on conventional radiographs. All assessments were done pre-operatively and at 2-year follow up. The series included 48 consecutive TKA (21 men, 27 women) performed at a single high-volume joint-replacement-center in 2008. All operations were performed using a tibia first-ligament balancing technique without patella resurfacing. The implant used was a condylar unconstrained ultracongruent rotating platform design. Outcome was assessed using the international knee society score (KSS) and the Kujala Score for anterior knee pain. Results. Preoperative CTA showed 6.4±2. 5° (X±SD) of internal femoral rotation (IR) (range, 1° of external rotation (ER) to 12° of IR) compared to postoperative CTA of 3.9°±2.98° (X±SD) of IR (range, 9.5° IR to 3.8°of ER) Preoperative patella lateral displacement showed a mean of 1.1mm (−2mm, 6mm), compared to postoperative patella lateral displacement with a mean of 1.7mm (−3mm, 6mm). Postoperative mean patella tilt was 6.65° (1.8°, 11.7°) postoperatively compared to 8.55° (4.3°,11.5°) preoperatively. No correlation was found between CTA post surgery and patella positioning (r=0.034, 95% CI). IR of the femoral component >3°did not show increased patella lateral displacement/tilt compared to 0° or ER. No correlation was found between the Kujala score and internal rotation of the component (r=0.082, p=0.05). At 2 year post OP KSS reached > 185 of max. 200 points in over 82% of patients. Conclusion. The influence of IR of the femoral component on patellofemoral
Introduction. Osteoarthritis (OA) represents a leading cause of disability and a growing burden on healthcare budgets. OA is particularly vexing for young, active patients who have failed less invasive therapies but are not yet candidates for arthroplasty. Often, patients suffering in this wide therapeutic gap face a debilitating spiral of disease progression, increasing pain, and decreasing activity until they become suitable arthroplasty patients. An implantable load absorber was evaluated for the treatment of medial knee OA in this patient population. Joint overload has been cited as a contributor to OA onset or progression. In response, the KineSpring® System (Moximed, Inc, USA) has been designed to reduce the load acting on the knee. The absorber is implanted in the subcutaneous tissue without violating the joint capsule, thus preserving the option of future arthroplasty. The implant is particularly useful for young, active patients, given the reversibility of the procedure and the preservation of normal flexibility and range of motion. Methods and Results. The KineSpring System was implanted in 55 patients, with the longest duration exceeding two years. The treated group had medial knee OA, included younger OA sufferers (range 31–68 years), with a mean BMI > 30kg/m2. Acute implant success, adverse events, and clinical outcomes using validated patient reported outcomes tools were recorded at baseline, post-op, 2 and 6 weeks, and 3, 6, 12 and 24 months post-op. All patients were successfully implanted with a mean procedure time of 76.4 min (range 54–153 minutes). Mean hospital length of stay was 1.7 days (range 1–3 days), and patients recovered rapidly, achieving full weight bearing within 1–2 wks and normal range of motion by 6 weeks. Most patients experienced pain relief and functional improvement with 85% (35/41) reporting none or mild pain on the WOMAC pain subscale and 90% (37/41) reporting functional impairment as none on mild on the WOMAC function subscale at the latest follow-up visit (mean 9.3 ± 3.5 months). Clinically meaningful and statistically significant pain reduction and functional improvement were noted with baseline WOMAC pain scores (0–100 scale) improving from 42.4 to 16.1 (p<0.001) and WOMAC function (0–100 scale) improving from 42.0 to 14.7 (p<0.001) at latest follow-up. Patients reported satisfaction with the implant and its appearance. Conclusions. The KineSpring System preserves natural knee anatomy and
Introduction. Minimally invasive implanted unicompartmental knee arthroplasty (UKA) leads to excellent functional results. Due to the reduced intraoperative visibility it is difficult to remove extruded bone cement particles, as well as bone particles generated through the sawing. These loose third body particles are frequently found in minimally invasive implanted UKA. The aim of this study was to analyse the influence of bone and cement particles on the wear rate of unicompartmental knee prostheses in vitro. Material & Methods. Fixed- bearing unicompartmental knee prostheses (n = 3; Univation F®, Aesculap, Tuttlingen) were tested with a customized four-station servo-hydraulic knee wear simulator (EndoLab GmbH, Thansau, Germany) reproducing exactly the walking cycle as specified in ISO 14243-1:2002. After 5.0 million cycles crushed cortical bone chips were added to the test fluid for 1.5 million cycles to simulate bone particles, followed by 1.5 million cycles blended with PMMA- particles (concentration of the third-body particles: 5g/l; particle diameter: 0.5- 0.7 mm). Every 500 000 cycles the volumetric wear rate was measured (ISO 14243-2) and the knee
The aim of this study was to investigate the effect of a posterior
malleolar fragment (PMF), with <
25% ankle joint surface, on
pressure distribution and joint-stability. There is still little
scientific evidence available to advise on the size of PMF, which
is essential to provide treatment. To date, studies show inconsistent
results and recommendations for surgical treatment date from 1940. A total of 12 cadaveric ankles were assigned to two study groups.
A trimalleolar fracture was created, followed by open reduction
and internal fixation. PMF was fixed in Group I, but not in Group
II. Intra-articular pressure was measured and cyclic loading was
performed.Aims
Materials and Methods
In a randomised prospective study, 20 patients with intra-articular fractures of the distal radius underwent arthroscopically- and fluoroscopically-assisted reduction and external fixation plus percutaneous pinning. Another group of 20 patients with the same fracture characteristics underwent fluoroscopically-assisted reduction alone and external fixation plus percutaneous pinning. The patients were evaluated clinically and radiologically at follow-up of 24 months. The Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire and modified Mayo wrist score were used at 3, 9, 12 and 24 months postoperatively. In the arthroscopically- and fluoroscopically-assisted group, triangular fibrocartilage complex tears were found in 12 patients (60%), complete or incomplete scapholunate ligament tears in nine (45%), and lunotriquetral ligament tears in four (20%). They were treated either arthroscopically or by open operation. Patients who underwent arthroscopically- and fluoroscopically-assisted treatment had significantly better supination, extension and flexion at all time points than those who had fluoroscopically-assisted surgery. The mean DASH scores were similar for both groups at 24 months, whereas the difference in the mean modified Mayo wrist scores remained statistically significant. Although the groups are small, it is clear that the addition of arthroscopy to the fluoroscopically-assisted treatment of intra-articular distal radius fractures improves the outcome. Better treatment of associated intra-articular injuries might also have been a reason for the improved outcome.