All patients were evaluated clinically (AOFAS score), radiographically and by MRI pre-operatively and at established intervals up to a mean follow-up of 119+/−6.5 months. At the final follow-up MRI T2 mapping evaluation was performed. A bioptic sample was harvested in 5 cases during hardware removal 12 months after implantation.
Bioptic samples showed cartilaginous features at various degrees of remodelling, positivity for collagen type II and for proteoglycans expression. No degenerative changes of the joint at follow-up were found radiographically. MRI showed well-modelled restoration of the articular surface. The regenerated cartilage showed a mean T2 mapping value of 46 msec with no significant difference compared to that of normal hyaline cartilage.
Metal-polycarbonate urethane (MPU) bearing is a cutting-edge new bearing technology for hip reconstruction. It consists of a 3mm-thick pliable acetabular cup which biomechanically mimics human cartilage and can be coupled with large diameter metal heads. In pristine sockets, no acetabular bone reaming is required to insert the cup. No cement is needed and the cup is simply snapped by hand into a groove made with a special tool. In deformed sockets, the standard reaming technique must be used. The cup acts as a liner inserted into an uncemented metal shell. MPU bearing has been analysed in comparative in vitro studies. Clinical and radiographic results have been recorded at a minimum follow-up of 2 years in 202 femoral neck fracture patients. Polycarbonate-urethane elasticity is 20MPa (70 times less than UMHWPE, 10,500 times less than CoCr, p <
0.001). The number of particles generated per step is 1000 with MPU, 1,000,000 with ceramic-ceramic and metal-metal (MOM) (p<
0.001). Fluid film thickness is 0.25microns with MPU, 0.02 with MOM (p<
0.001). At a minimum follow-up of 2 years, X-rays showed good implant stability. In sockets where the buffer alone was implanted an improvement of the supraacetabular bone density was observed over time. Mean Harris hip score after 1 month was 58 points, increasing to 80 points at 2 years (p <
0.05). One patient was revised, due to non-implant-related pain. The in vitro and clinical data support the use of this novel bearing technology which has the potential to revolutionize hip arthroplasty.
Metal-on-metal hip resurfacing (MOMHR) is a good surgical indication for young active patients. However, it cannot be used in patients with severe CDH and in particular a too short head/neck. To address these cases, a new surgical technique consisting of augmentation of the femoral head with impacted morcellized bone grafts has been developed. 32 osteoarthritis patients following severe congenital insufficiency of the femoral head/neck were treated with MOMHR combined with femoral head augmentation. The required amount of augmentation was calculated on preoperative X-rays and confirmed during surgery. Using special instrumentation, bone chips produced while reaming the socket and trimming the head were impacted on the head to achieve the desired reconstruction and lengthening. Finally, the femoral component was cemented. Mean patient age was 49+ 9 years (18–66). Median head lengthening was 12+ 2 mm. Mean follow up is 4.2 years (3–6). Mean preoperative Harris hip score (HHS) was 58 and at follow-up 95 (p <
0.05). Mean leg lengthening was 2.2 cm (p = 0.001). In all Gruen zones, bone mineral density (BMD) decreased during the first 3 months. At 2 years in zone 1 mean BMD increased to 96.8% (p = 0.009) and in zone 7 to 102.1% (p = 0.05). A correlation was found between valgus positioning of the femoral components and increased BMD (p = 0.005). This impaction bone grafting technique expands the use of MOMHR to patients with severe congenital hip dysplasia leading to a more anatomical reconstruction with a full recovery of function and BMD.
A linkage-based mathematical model was used to design a ligament-compatible prosthesis to keep certain ligament fibres isometric during passive motion. The sagittal plane talar component radius is about 50% longer than that of the normal talus, the tibial component is spherically convex. A fully conforming meniscal bearing is interposed between them. Experiments in cadaver specimens confirmed the mathematical prediction that the bearing moves forwards on both metal components during dorsi-flexion and backwards during plantar flexion. Between July 2003 and July 2008, the prosthesis was implanted into 250 patients at nine hospitals in Northern Italy. By November 2007, 158 in 156 patients were seen at least six months post-operatively. Mean age was 60.5 years. The diagnosis was post-traumatic osteoarthritis in 127, primary osteoarthritis in 17, rheumatoid arthritis in 10. The mean follow-up was 32.5 months. The pre-operative AOFAS score of 36.2 rose to 75.9, 79.3, 77.9, and 79.0 respectively at 12, 24, 36, 48 months. Dorsi-flexion increased from 0.1° to 9.7°, plantarflexion from 15.1° to 24.6°. In 30 patients at one hospital, the range of postoperative motion, 14° – 53°, was significantly correlated to the range of bearing movement on the tibial component, 2mm–11mm, measured radiologically, (r2 = 0.37, p <
0.0005). By December 2007, 2 revision operations had been performed at 24 months, one for unexplained pain not relieved by a successful arthrodesis, one in a patient with Charcot-Marie-Tooth disease. There were no device-related revisions (loosening, fracture, dislocation). The Kaplan-Meier survival rate (component-removal as end-point) at 4 years was 96% (Confidence interval 90–100%). Early clinical results have demonstrated safety and efficacy. The survival rate at four years compares well with multi-centre 5-year rates published by the Swedish (531 cases, survival 78%), Norwegian (257, 89%) and New Zealand (202, 86%) registries.
Arthrodesis was performed through a 2.5 cm incision, with partial cartilage removal and insertion of a structural corticocancellous block (2 × 1cm), harvested from the proximal ipsilateral tibia, vertically positioned into the sinus tarsi. Associate procedures were Achilles tendon lengthening (124), SERI procedure (61), hind-foot deformity correction (32). Postoperatively plaster-cast without weight-bearing for 4 weeks followed by walking boot was advised. All patients were reviewed at a minimum follow-up of 5 years.
Anterior bony impingement of the ankle is a common cause of chronic ankle pain, and it represents an important indication to arthroscopic treatment. The purpose of the study was to analyze the factors affecting the clinical outcome of surgical treatment and to describe a new classification based upon the arthroscopic assessment, considering prognostic factors and rationale for treatment. 84 consecutive patients with a mean age of 32.6 years were treated between 2000 and 2005. The impinging lesions were divided into localized (antero-medial, antero-lateral and syndesmotic) or diffuse. The status of the chondral layer (A – Normal; B – Focal ICRS grade I–II; C - Focal ICRS grade III–IV; D – Diffuse ICRS grade I–II; E – Diffuse ICRS grade III–IV) was documented, as well as the presence of altered foot morphology (cavus or flat) or ligament lesions. Previous traumas or surgery were considered. Patients were evaluated after a 24–87 months follow-up, following the AOFAS scale. The pre-operative AOFAS score was 39.4, while at follow-up it scored 80.1(p<
0.05). Patients with diffuse anterior impingement obtained the best result in terms of improvement. Patients with normal cartilage had a better outcome but among cartilage lesions the better improvement was obtained in patients with diffuse severe cartilage damage. Associated regenerative treatment for focal chondral grade III–IV lesions provided the better results. Patients with associated surgically repaired ligament lesions had the better clinical outcome with respect to intact ligaments. On the basis of the results we purpose a new classification, based upon the prognostic factors, into 2 types: I – Localized; II - Diffuse. Further classification was made into subtypes A to E according to the associated chondral lesions. Finally the presence of associated conditions such as ligament lesions, previous sprains or surgery was considered, being relevant as prognostic factors.
The aim of this study is to present guidelines for treatment of acquired adult flat foot (AAFF) and review the results of a series of patients consecutively treated. 180 patients (215 feet), mean age 54? 12 years affected by AAFF were evaluated clinically, radiographically and by MRI to chose the adequate surgical strategy. Tibialis posterior dysfunctions grade 1 were treated by tenolysis and tendon repair (48 cases), grade 2 by removal of degenerated tissue and tendon augmentation (41 cases), grade 3 by flexor digitorum longus tendon transfer (23 cases); in these cases subtalar pronation without arthritis was corrected by addictional procedures consisting of either calcaneal osteotomy (66 cases), subtalar athroereisis (25 cases) or Evans procedure (21 cases) in case of severe midfoot abduction. Subtalar arthrodesis (82 cases) or triple arthrodesis (21 cases) were performed in case of subtalar arthritis isolated or associated with midtarsal arthritis respectively. Postoperatively plastercast without weight-bearing for 4 weeks followed by walking boot for 4 weeks was advised. All patients were followed up to 5 years. Before surgery the mean AOFAS score was 48+\−11, while it was 89+\−10 at follow-up (p<
0.005). Mean heel valgus deviation at rest was 15°+\−5° preoperatively and 8°+\−4° at follow-up (p<
0.005). Mean angulation of Meary’s line at talonavicular joint level was 165°+\−12° preoperatively and 175°+\6 at follow-up. Surgical strategy in AAFF should include adequate treatment of tibialis posterior disfunction and osteotomies for correction of the skeletal deformities if joints are arthritis free; arthrodesis should be considered in case of severe joint degeneration
Knowing patient bone density is important to select the proper fixation technique and for secondary osteoporosis medical treatment. However few studies addressing hip fractures provided data regarding patient bone mineral density.
Discussion: There are notable differences in bone mass density. Femoral neck BMD proved to be the best diagnostic site using DXA, with 15.07% of hip fracture patients having a normal age-related bone mass. Higher non-osteoporotic bone densities were found in women with hip fractures: BMD values were (27.40%) at the trochanter and (17.81%) at the Ward’s triangle.
(a) To choose the tendon grafts considering the donors’ characters; (b) To use fresh tendons; (c) To test the controlateral tendon from the same donor before use.
All treatment emergent adverse events (AEs) were recorded. The primary efficacy endpoint was change from baseline (at final injection) in the Ankle OA Pain VAS at 3 months after the final injection. Secondary endpoints were Ankle OA Pain VAS scores at all other time-points, total Ankle OA Scale, Patient and Physician Global OA Assessment (VAS), and health-related quality of life (SF-36).
A new design of total ankle replacement was developed. According to extensive prior research, the design features a spherical convex tibial component, a talar component with radius of curvature in the sagittal plane longer than that of the natural talus, and a meniscal component fully conforming to these two. The shapes of the tibial and talar components are compatible with a physiologic ankle mobility and with the natural role of the ligaments. Within an eight-centre clinical trial, 114 patients were implanted in the period July 2003 – September 2006, with mean age 62.2 years (range 29 – 82). The AOFAS clinical score systems and standard radiographic assessment were used to assess patient outcome, here reported only for those 75 patients with follow-up longer than 6 months. Intra-operatively, the components maintained complete congruence at the two articulating surfaces of the meniscal bearing over the entire motion arc, associated to a considerable anterior motion in dorsiflexion and posterior motion in plantarflexion of the meniscal-bearing, as predicted by the previous mathematical models. Mean 10.0 and 23.5 degrees respectively of dorsi- and plantar-flexion were measured immediately after implantation, for a mean additional range of motion of 19.2, which was maintained at follow-ups. Radiographs showed good alignment and no signs of evolutive radiolucency or loosening. The mean AOFAS score went from 40.8 pre-op to 66.2, 74.6 and 77.2 respectively at 3, 6 and 12 month follow-ups. One revision only was performed successfully three days after implantation because of a technical error. In the score system utilized, Function and RoM sections scored better than any average previous total ankle result, Pain scored similarly. The satisfactory though preliminary observations from this novel design encourage continuation of the implantation, which is now extended over a few European countries. Instrumented gait and three-dimensional fluoroscopic analyses are in progress to quantify functional progresses.
Navigation-assisted surgery in total knee arthroplasty (TKA) is aimed at improving the accuracy with which prosthesis components are implanted in the bones, according to anatomical plane orientations. Traditional surgical techniques based on the identification of transepicondylar and intramedullary axes are replaced with those based on segmental anatomical frame definitions following anatomical landmark identification. These frames are offered on the screen to the surgeon to target in real time the alignment goal by adjusting position and orientation of the bone saw guides. However, immediately after sawing, final bone, and in case cement, preparation and component implantation is necessarily a series of actions performed manually by the surgeon. In the current study, we wanted to compare intra-operatively the final component alignments with the corresponding at the original resection planes. In this series, 50 Scorpio PS TKAs were analyzed. The navigation system used was the Stryker Knee Navigation System (Stryker-Navigation, Kalamazoo, USA). An ‘anatomical survey’ defined anatomical frames for the femur and tibia, based on relevant anatomical landmark identification, and provided target orientations for all the relevant bone cuts. These references were targeted in all three anatomical planes, and bone cuts were made accordingly. Corresponding alignments of the bone resection planes in the frontal, sagittal and transverse planes for the femur and in the frontal and sagittal planes for the tibia were recorded, with a 0.5° resolution. Then, component implantation was performed and alignments were measured again by means of an instrumented probe. Because of the shape of the prosthesis components, only the alignments in the frontal plane for the femur and in the frontal and sagittal planes for the tibia were recorded. The difference between the alignment of the bone cuts and the alignment of the prosthesis components, in the frontal plane of the femur, and in the frontal and sagittal planes of the tibia was larger than 2° respectively in 8%, 6%, 10% of the patients. The present study offers a figure for the different alignment between resection planes and final implanted components, necessarily the effect of the manual procedures implied in TKA for the final implantation of the components. Considering that 1° is the claimed achievable accuracy of the navigation systems, and that the correct alignment goal was achieved at the resection planes, these figures reveal that in up to 10% of the patients the benefit obtained by navigation can be lost by the manual procedures implied in component implantation. These differences in alignment put also concerns in the postoperative statistical comparison between conventional and navigated TKAs.
Functional outcome in Total Knee Arthroplasty (TKA), as measured by means of gait analysis for kinematics, kinetics, and muscular activity around the knee shows abnormalities even in patients with excellent clinical outcome. Knee flexion during loading response phase is reduced, accompanied by co-contraction of knee extensors and flexors. Such subtle failure in knee performance during loading absorption was claimed to depend on several factors: quadriceps weakness, prosthetic design, pre-surgical pattern, proprioception disruption. It was supposed to damage the implant in time. The lack of the anterior cruciate legament seems to play a major role in the loss of control of the roll back pattern of the condyles on the tibial plateau in TKA patients. Previous works on unicondylar knee artrhoplasty (UKA) demonstrated better gait performance when anterior cruciate ligament was preserved allowing the patients to maintain normal quadriceps mechanics. The aim of the present work is to evaluate UKA patients knee function during gait compared to TKA with the hypothesis that UKA ensures more physiological knee loading response pattern of movement and a more phasic muscular activation, thus reducing the risk of failure. Twenty patients with Oxford/Exactech UKA (mean age 70 (SD 7.9), mean follow-up 2 years) were evaluated by means of a Vicon 612-8 cameras system, two Kistler forceplates and Telemg respectively for knee 3D kinematics, kinetics and muscular activity. Data of UKA were compared to those of a control population of ten healthy subjects and ten patients with TKA matched for age and follow up. Mean UKA-IKS score at the time of gait analysis was 90. Time-distance parameters evidenced a slight slow gait with reduced stride length and cadence and a symmetric longer stance phase with respect to TKA and controls. Knee kinematics on the sagittal plane showed knee flex-ion during loading response very close to controls and a reduced but phasic pattern of joint moments on the sagittal plane. Adduction moment at the knee was normal. EMG showed controversy results as some patients had a regular pattern of activation of rectus femoris and hamstrings without co-contraction whereas other patients had co-contraction. These preliminary results indicate that UKA allows in most patients a quite normal knee kinematics and kinetics, although some abnormalities persist in quadriceps activation. Further research is required to understand these findings assessing other factors which could influence quadriceps activity such as age, proprioception, and muscular strength.