The flat foot is a frequent deformity in children and results in various levels of functional alterations. A diagnosis based on foot morphology is not sufficient to define the therapeutic approach. In fact, the degree of severity of the deformity and the effects of treatments require careful functional assessment. In case of functional flatfoot, subtalar arthroereisis is the surgical treatment of choice. The aim of this study is to evaluate and compare the functional outcomes of two different bioabsorbable implants designed for subtalar arthroereisis in childhood severe flat foot by means of thorough gait analysis.

Ten children (11.3 ± 1.6 yrs, 19.7 ± 2.8 BMI) were operated for flat foot correction [1,2] in both feet, one with the calcaneo-stop method, i.e. a screw implanted into the calcaneus, the other with an endoprosthesis implanted into the sinus-tarsi. Gait analysis was performed pre- and 24 month post-operatively using a 8-camera motion system (Vicon, UK) and a surface EMG system (Cometa, Italy) to detect muscular activation of the main lower limb muscles. A combination of established protocols, for lower limb [3] and multi-segment foot [4] kinematic analysis, was used to calculate joint rotations and moments during three level walking trials for each patient. At the foot, the tibio-talar, Chopart, Lisfranc, 1^st metatarso-phalangeal joints were tracked in three-dimensions, together with the medial longitudinal arch.

Significant differences in standard X-ray measurements were observed between pre- and post-op, but not between the two treatment groups. Analysis of the kinematic variables revealed functional improvements after surgery. In particular, a reduction of eversion between the shank and calcaneus (about 15° on average) and a reduction of inversion between metatarsus and calcaneus (about 18° on average) were detected between pre- and post-operatively after both treatments. Activation of the main plantar/dorsiflexor muscles was similar at both pre- and post-op assessments with both implants.

The combined lower limb and multi-segment foot kinematic analyses were found adequate to provide accurate functional assessment of the feet and of the lower limbs. Both surgical treatments restored nearly normal kinematics of the foot and of the lower limb joints, associated also to a physiologic muscular activation.

INTRODUCTION

In total knee arthroplasty (TKA), the effectiveness of the mechanical alignment (MA) within 0°±3° has been recently questioned. A novel implantation approach, i.e. the kinematic alignment (KA), emerged recently, this being based on the pre-arthritic lower-limb alignment. In KA, the trans-cylindrical axis is used as the reference, instead of the trans-epicondylar one, for femoral component alignment. This axis is defined as the line passing through the centres of the posterior femoral condyles modeled as cylinders. Recently, patient specific instrumentation (PSI) has been introduced in TKA as an alternative to conventional instrumentation. This provides a tool for preoperative implant planning also via KA. Particularly, KA using PSI seems to be more effective in restoring normal joint kinematics and muscle activity.

The purpose of this study was to report preliminarily joint kinematic and electromyography results of two patient groups operated via conventional MA or KA, the latter using PSI.

Objectives

The period of post-operative treatment before surgical wounds are completely closed remains a key window, during which one can apply new technologies that can minimise complications. One such technology is the use of negative pressure wound therapy to manage and accelerate healing of the closed incisional wound (incisional NPWT).

INTRODUCTION

In computer-aided total knee arthroplasty (TKA), surgical navigation systems (SNS) allow accurate tibio-femoral joint (TFJ) prosthesis implantation only. Unfortunately, TKA alters also normal patello-femoral joint (PFJ) functioning. Particularly, without patellar resurfacing, PFJ kinematics is influenced by TFJ implantation; with resurfacing, this is further affected by patellar implantation. Patellar resurfacing is performed only by visual inspections and a simple calliper, i.e. without computer assistance.

Patellar resurfacing and motion via patient-specific bone morphology had been assessed successfully in-vitro and in-vivo in pilot studies aimed at including these evaluations in traditional navigated TKA.

The aim of this study was to report the current experiences in-vivo in two patient cohorts during TKA with patellar resurfacing.

INTRODUCTION

In Total Knee Arthroplasty (TKA), the neutral overall limb alignment (NOLA), i.e. the mechanical alignment of the lower limb within 0°±3°, is targeted for achieving good clinical/functional results. The kinematic overall limb alignment (KOLA), which uses the axis through the centres of the femur posterior condyles modelled as cylinders, represents a novel approach for achieving better soft tissue balance.

Patient-specific instrumentation (PSI) is nowadays offered as an effective technology in TKA to obtain better lower limb alignments than those via conventional guides (CON). Although relevant results are still inconsistent, the benefits claimed include shorter operative time, reduced surgical instrumentation, and accurate preoperative planning.

The aim of this study was to report the preliminary clinical and radiological results of TKA patients operated via NOLA-PSI and KOLA-PSI. Comparisons between them and with the results obtained via NOLA-CON were performed.

We undertook a randomised controlled trial to compare bipolar hemiarthroplasty (HA) with a novel total hip replacement (THR) comprising a polycarbonate–urethane (PCU) acetabular component coupled with a large-diameter metal femoral head for the treatment of displaced fractures of the femoral neck in elderly patients. Functional outcome, assessed with the Harris hip score (HHS) at three months and then annually after surgery, was the primary endpoint. Rates of revision and complication were secondary endpoints.

Based on a power analysis, 96 consecutive patients aged > 70 years were randomised to receive either HA (49) or a PCU-THR (47). The mean follow-up was 30.1 months (23 to 50) and 28.6 months (22 to 52) for the HA and the PCU group, respectively.

The HHS showed no statistically significant difference between the groups at every follow-up. Higher pain was recorded in the PCU group at one and two years’ follow-up (p = 0.006 and p = 0.019, respectively). In the HA group no revision was performed. In the PCU-THR group six patients underwent revision and one patient is currently awaiting re-operation. The three-year survival rate of the PCU-THR group was 0.841 (95% confidence interval 0.680 to 0.926).

Based on our findings we do not recommend the use of the PCU acetabular component as part of the treatment of patients with fractures of the femoral neck.

Cite this article: Bone Joint J 2013;95-B:609–15.

Introduction

In elderly patients, the incidence of a second fracture in the contralateral hip within 2 years of a femoral neck fracture (FNF), ranges from 7 to 12%.

Introduction

The delay looks radiographically as a fracture callus not very evident or absent 6 months after osteosynthesis. Patients undergo a long period of immobilization and this fact causes the increase the social cost of the disease. The technique we suggest aims to the reduce the period of immobilization and as a consequence the management costs of the disease.

INTRODUCTION

Despite a large percentage of total knee arthroplasty failures occurs for disorders at the patello-femoral joint (PFJ), current navigation systems report tibio-femoral (TFJ) kinematics only, and do not track the patella. Despite this tracking is made difficult by the small bone and by its full eversion during surgery, a new such technique has been developed, which includes a new tracker, new corresponding surgical instrumentation also for patellar resurfacing, and all relevant software. The aim of this study is to report an early experience in patients of these measurements, i.e. TFJ and PFJ kinematics.

Restoration of natural range and pattern of motion is the primary goal of joint replacement. In total ankle replacement, proper implant positioning is a major requirement to achieve good clinical results and to prevent instability, aseptic loosening, meniscal bearing premature wear and dislocation at the replaced ankle. The current operative techniques support limitedly the surgeon in achieving a best possible prosthetic component alignment and in assessing proper restoration of ligament natural tensioning, which could be well aided by computer-assisted surgical systems. Therefore the outcome of this replacement is, at present, mainly associated to surgeon's experience and visual inspection. In some of the current ankle prosthetic designs, tibial component positioning along the anterior/posterior (A/P) and medio/lateral axes is critical, particularly in those designs not with a flat articulation between the tibial and the meniscal or talar components. The general aim of this study was assessing in-vitro the effects of the A/P malpositioning of the tibial component on three-dimensional kinematics of the replaced joint and on tensioning of the calcaneofibular (CaFiL) and tibiocalcaneal (TiCaL) ligaments, during passive flexion. Particularly, the specific objective is to compare the intact ankle kinematics with that measured after prosthesis component implantation over a series of different positions of the tibial component.

Four fresh-frozen specimens from amputation were analysed before and after implantation of an original convex-tibia fully-congruent three-component design of ankle replacement (Box Ankle, Finsbury Orthopaedics, UK). Each specimen included the intact tibia, fibula and ankle joint complex, completed with entire joint capsule, ligaments, muscular structures and skin. The subtalar joint was fixed with a pin protruding from the calcaneus for isolating tibiotalar joint motion. A rig was used to move the ankle joint complex along its full range of flexion while applying minimum load, i.e. passive motion. In these conditions, motion at the ankle was constrained only by the articular surfaces and the ligaments. A stereofotogrammetric system for surgical navigation (Stryker-Leibinger, Freiburg, Germany) was used to track the movement of the talus/calcaneus and tibial segments, by using trackers instrumented with five active markers. Anatomical based kinematics was obtained after digitization by an instrumented pointer of a number of anatomical landmarks and by a standard joint convention. The central point of the attachment areas of CaFiL e TiCaL was also digitised. Passive motion and ankle joint neutral position were acquired, and the standard operative technique was performed to prepare the bones for prosthesis component implantation. The final component for the talus was implanted, the tibial component was initially positioned well in front of the nominal right (NR) position, the meniscal bearing was instrumented with an additional special tracker, and passive motion was collected again in passive flexion. Data collection was repeated for progressively more posterior locations for the tibial component, for a total of six different locations along the tibial A/P axis: three anterior (PA), the NR, and two more posterior (PP), approximately 3 to 5 mm far apart each. The following three-dimensional kinematics variables were analyzed: the three anatomical components of the ankle joint (talus-to-tibial) rotation (dorsi/plantar flexion, prono/supination and internal/external rotation respectively in the sagittal, frontal and transverse planes), the meniscal bearing pose with respect to the talar and tibial components, the ‘ligament effective length fraction’ as the ratio between the instantaneous distance between the ligament attachment points and the corresponding maximum distance, and the instantaneous and mean helical axes in the tibial anatomical reference frame.

In all specimens and in all conditions, physiological ranges of flexion, prono/supination and internal/external rotation were observed at the ankle joint. A good restoration of motion was observed at the replaced joint, demonstrated also by the coupling between axial rotation and flexion and the physiological location of the mean helical axis, in all specimens and in most of the component positions. Larger plantar- and smaller dorsi-flexion were observed when the tibial component was positioned more anteriorly than NR, and the opposite occurred for more posterior positions. In regards to the meniscal bearing, rotations were small and followed approximately the same patterns of the ankle rotations, accounted for the full conformity of the articulating surfaces. Translations in A/P were larger than in other directions, the bearing moving backward in plantarflexion and forward in dorsiflexion with respect to both components. It was observed that the closer to NR the position of the tibial component is, the larger this A/P motion is, accounted mainly to the associated larger range of flexion. The change of CaFiL and TiCaL effective length fraction over the flexion arc was found smaller than 0.1 in three specimens, smaller than 0.2 in the fourth, larger both in more anterior and more posterior locations of the tibial component. The simulated malpositioning did not affect much position and orientation of the mean helical axis in both the transversal and frontal planes.

The experimental protocol and measurements were appropriate to achieve the proposed goals. All kinematics variables support the conclusion that the ankle replaced with this original prosthesis behaves as predicted by the relevant computer models, i.e. physiological joint motion and ligament tension is experienced resulting in a considerable A/P motion of the meniscal bearing. These observations are particularly true in the NR postion for the prosthesis, but are somehow correct also in most of the tibial malpositions analysed, in particular those on the back.

Introduction

Multiple ACL revisions represent an extremely demanding surgery, due to the presence of enlarged or malpositioned tunnels, hardware, injuries to the secondary stabilizers and difficulties in retrieving autologous tendons. An anatomical ACL reconstruction is not always possible. We analyzed the results in a series of patients operated with over the top reconstruction (OTTR) and lateral extra-articular plasty to the Gerdy's tubercle (LP) using Achilles (AT) or tibialis posterior tendon (TPT) allografts.

Osteocondritis dissecans (OCD) is a relatively common cause of knee pain. Ideal treatment is still controversial. Aim of this exhibit is to describe the outcomes of 5 different surgical techniques in a series of 63 patients.

63patients (age 22.5±7.4 years) affected by OCD of the femoral condyle (45 medial and 17 lateral) were treated by either osteochondral autologous transplantation, autologous chondrocyte implantation with bone graft, biomimetic nanostructured osteochondral scaffold (Maioregen) implantation, bone-cartilage paste graft or bone marrow derived cells transplantation “one-step” technique. Patient evaluation included IKDC score, eq-vas score, X-Rays and MRI preoperatively and at follow-up.

Global mean IKDC improved from pre-operative 40.1±14.6 to 77.2±21.3 (p<0.0005) at mean 5.3±4.7 years follow-up, while eq-vas improved from 51.7±17.0 to 83.5±18.3(p<0.0005). No influence of age, size of the lesion, length of follow-up and associated surgeries on the result was found. No differences were found between the results obtained with different surgeries except a slight tendency of better improvement in the result following autologous chondrocyte implantation (p<0.01). Control MRI evidenced a satisfactory repair of cartilaginous layer and subchondral bone.

The techniques described were effective in providing good clinical and radiographic results in the treatment of OCD and confirmed the validity of autologous chondrocyte implantation over time. Newer techniques such as Maioregen implantation and “one-step” base on different rationales, the first relying on the characteristics of the scaffold and the second on the regenerative potential of mesenchymal cells. Both of them have the advantages to be minimally invasive surgeries and to require a single operation.

Objective

High grade hallux rigidus is a forefoot deformity characterized by a limitation of dorsiflexion of the first toe associated with pain, and severe damage of the first metatarsophalangeal joint. Most authors recommended resection arthroplasty or arthrodesis of the first metatarsophalangeal joint. The aim of this study was to present the results of our series of 42 consecutive cases of severe hallux rigidus treated by resection of the first metatarsal head and implant of a poly D-L lactic (PDLLA) bioreabsorbable spacer to promote the interposition of fibrous tissue to preserve the range of motion of the joint.

Introduction

Metal-on-metal hip resurfacing (MOMHR) is a good surgical indication for young active patients. However, it cannot be used in patients with an excessively short femoral head/neck. To address these cases, a new surgical technique has been developed comprising femoral head augmentation using impacted morcellized bone grafts.

Objective

Combined metatarso-phalangeal and inter-phalangeal deformity represents about 1% of hallux valgus deformity, and its treatment remains a debated topic, because a single osteotomy does not entirely correct the deformity and double osteotomies are needed. The aim of this study is to review the results of 50 consecutive combined metatarso-phalangeal and inter-phalangeal hallux valgus treated by Akin proximal phalangeal osteotomy and SERI minimally invasive distal metatarsal osteotomy.

Computer-assisted techniques in total knee replacement (TKR) have been introduced to improve bone cuts execution and relevant prosthesis components positioning. Although these have resulted in good surgical outcomes when compared to the conventional TKR technique, the surgical time increase and the use of additional invasive devices remain still critical. In order to cope with these issues, a new technology in TKR has been introduced also for positioning prosthetic components according to the natural lower-limb alignment. This technique is based on custom-fit cutting block derived from patient-specific lower-limb scan acquisition. The purpose of this study is to assess the accuracy of the custom-fit technology by means of a knee surgical navigation system, here used only as measurement system, and post-operative radiographic evaluations. Particularly, the performances of two different custom-fit cutting blocks realized from as many scan acquisitions have been here reported.

Thirty patients affected by primary knee osteoarthritis were enrolled in this study. Fifteen patients were implanted with GMK® (Medacta-International, Castel San Pietro, CH) and as many patients with Journey® (Smith&Nephew, London, UK). Both TKR designs were implanted by using custom-fit blocks for bone cut executions provided by the same TKR manufacturers according to a pre-operative web planning approved by the surgeon. Particularly, the cutting block for the former design was built from CT scan acquisition of the hip, knee and ankle, whereas that for the latter design from MRI scans acquisition of the knee and X-ray lower-limb overview. A knee surgical navigation system (Stryker®-Leibinger, Freiburg, Germany) was used for recording intra-operative alignment of bone cuts as performed by means of the custom-fit cutting blocks and relevant component positioning. Prosthetic components alignments were also assessed post-operatively on X-ray images according to a shape-matching technique. The accuracy of the custom-fit blocks was evaluated through the comparison between pre-operative planning, and intra/post-operative data. Discrepancies above 3° and millimeters were considered as outliers.

Within the patient cohort, nine cases were fully analyzed at the moment and here reported. Over them and except for one case, the discrepancy between pre-operative planned femoral/tibial resection level on the frontal plane and the corresponding measured intra-operatively was within 3 mm, being 5 mm in the worse case. Two outliers were observed for the corresponding femoral/tibial cut rotational alignment. Particularly, in one patient, the discrepancy in femoral cut alignment was of 8° in flexion and 6° in external rotation; in another patient this was of 4° in extension and 4° in external rotation in the femoral and tibial cut alignment, respectively. Post-operative radiographs evaluations for the final prosthetic components revealed that femoral/tibial alignment were within 3° in all cases, except for those patients that were already outliers.

These preliminary results reveal the efficacy of the custom-fit cutting block for TKR. These were generally fitted properly and final prosthetic components were accurately placed, although some discrepancies were observed. This new technology seems to be a valid alternative to conventional and computer-assisted techniques. More consistent conclusions can be deduced after final evaluation of all patients.

ACL (anterior cruciate ligament) partial tears include various types of lesions, and an high rate of these lesions evolve into complete tears. Most of the techniques described in literature for the surgical treatment of chronic partial ACL tears, don't spare the intact portion of the ligament. Aim of this study was to perform a prospective analysis of the results obtained by augmentation surgery using gracilis and semitendinosus tendons to treat partial sub-acute lesions of the ACL. This technique requires an “over the top” femoral passage, which enables salvage and strengthening of the intact bundle of ACL. The study included 97 patients treated consecutively at our Institute from 1993 to 2004 with a mean injury-surgery interval of 23 weeks (12–39). Patients were followed up by clinical and instrumental assessment criteria at 3 months, 1 year and 5 years after surgery. Clinical assessment was performed with the IKDC form. Subjective and functional parameters were assessed by the Tegner activity scale. Instrumental evaluation was done using the KT-2000 instrument: the 30 pound passive test and the manual maximum displacement test were performed. We obtained good to excellent results in 95.9% of cases. We didn't observed recurrences in ligamentous laxity. We believe that the described technique has the advantage of being little invasive, compatible with the ACL anatomy, and enables very rapid functional recovery and return to sport.

INTRODUCTION

Fresh bipolar shell osteochondral allograft (FBOA) is a controversial treatment option for post-traumatic ankle arthritis. Immunological response to transplanted cartilage may play a role in failure. Aim of the study is to compare two groups of patients who received FBOA in association or not to immunosuppressive therapy.

Although the number of displaced femoral neck fractures treated with hip arthroplasty is steadily growing, the outcomes are not as good as for other surgical indications. As a result, there is no consensus on the ideal type of arthroplasty for these patients. Unipolar and bipolar arthroplasty have a low dislocation rate but implant longevity and functional results are suboptimal. Total hip arthroplasty (THA) provides better functional outcomes and implant longevity but it is associated with a high incidence of postoperative dislocation. This constitutes a significant limiting factor for a more widespread use of this procedure.

The TriboFit^® Buffer (Active Implants Corporation, Memphis, Tennessee, USA) is a 2.7 mm-thick cup made of polycarbonate-urethane which mimics the mechanical characteristics of human cartilage. It is a pliable, hydrophilic, biocompatible, endotoxin-resistant material and acts as a stress-absorber, transmitting loads to the subchondral bone in a physiological manner. The TriboFit^® Buffer shows excellent tribology, including ideal fluid film lubrication, low friction, high load carrying capabilities and long endurance.

The TriboFit^® Buffer is fixed using flexible mechanical fixation. With a special instrument, a circumferential groove is cut into the patients’ socket. The TriboFit^® Buffer is seated by applying gentle pressure, with its ledge snapping tightly into the groove. The surgical technique is bone sparing as no acetabular bone reaming is required whatsoever. The TriboFit^® Buffer can be coupled with large diameter cobalt-chromium femoral prosthetic heads of the same dimensions as the patients’ femoral head. By restoring the correct hip anatomy and preserving the original size of the femoral head, hip range of motion (ROM) and stability are optimised.

Within a multi-centre study, 224 patients (63 male and 161 female) with femoral neck fractures were treated with the TriboFit^® Buffer, a large diameter head and either cemented (192) or uncemented femoral stems (32). The mean patient age was 83 years (range 65 to 96).

All surgeries were performed using a standard antero-lateral approach.

Rehabilitation was fast and weight-bearing was as tolerated by the patients. There were no major complications, and in particular, no postoperative dislocations were reported.

At a mean follow-up of one year, X-rays showed good implant stability. The mean Harris hip score (HHS) after one month was 58 points and increased to 80 points at one year (p = < 0.05). The ROM was the same as in the intact hip. Only one patient was revised because of nonimplant-related pain. This patient complained of pain in the surgically treated limb which was in actual fact related to spinal stenosis. Analysis of the retrieved implant revealed a loss of thickness in the superior area as well as minimal weight (approximately 2.4%). The backside revealed evidence of macroscopic wear in the area of directional loading from the femoral head to the acetabulum. The bearing surface showed minimal wear (less than 15 mm3), indicating that the primary wear location was on the backside. Retrieved synovial fluid and tissue analysis confirmed that there was no reactivity and no sign of synovitis.

With femoral neck fracture patients, TriboFit^® Buffer arthroplasty is theoretically superior to both hemiarthroplasty and THA as it should involve the same low risk of dislocation and acetabular bone preservation associated with hemiarthroplasty, together with the same good functional results and consistent implant longevity of THA. Other advantages of this technique include reduced bleeding and short surgical times.

The results of this study show that the new TriboFit^® Buffer arthroplasty technology has the potential to revolutionize the surgical treatment of displaced femoral neck fracture.

Although metal-on-metal hip resurfacing (MOMHR) is becoming a well accepted indication for young active patients with hip deformities, it does not come without its disadvantages. Longterm bone atrophy, serum metal ion elevation, metal ion hypersensitivity and the formation of pseudotumours have all been reported in the literature. It is thus clear that there is a need for novel bearing technology.

A potentially revolutionary hip resurfacing system comes in the form of the TriboFit^® Hip System, which comprises a 2.7 mm-thick acetabular buffer made of polycarbonate-urethane, a hydrophilic, biocompatible, endotoxin-resistant material which mimics the fluid film layer naturally present in hip joints. This is a pliable implant whose modulus of elasticity is the same as that of normal human cartilage, thus providing optimum shock absorption. In addition, it induces lubrication, which is of the utmost importance as friction is almost eliminated, resulting in a subsequent decrease in the production of wear particles. Indeed, in vitro studies have shown that metal wear is 7-fold less than with a comparable metal-on-metal implant.

The TriboFit^® Buffer is implanted using flexible mechanical fixation. With a special instrument, a circumferential groove is cut into the patients’ socket. The TriboFit^® Buffer is seated by applying gentle pressure, with its ledge snapping tightly into the groove. The surgical technique is bone sparing as no acetabular bone reaming is required whatsoever. The TriboFit^® Buffer can be coupled with a select number of metal hip resurfacing femoral components.

In our centre, we have used this novel bearing technology to treat patients with both osteoarthritis (two patients) and avascular necrosis (four patients). The mean patient age was 50 years (range 30 to 63). In five patients who had a well preserved socket anatomy, the TriboFit^® Buffer was implanted without reaming the acetabular bone. In one patient with significant osteoarthritic changes of the socket, the TriboFit^® Buffer was inserted into a specially manufactured uncemented metal shell, using the TriboFit^® Buffer as a liner. The socket was reamed according to the standard reaming technique. In two patients a Birmingham hip resurfacing (BHR) femoral component was used and in the other four an ADEPT component was used.

Rehabilitation was fast and uncomplicated. The mean follow-up of these patients was one year. The mean preoperative Harris hip score (HHS) was 62. The mean HHS at one year was 99 (p = < 0.05). X-rays showed good quality bone at the bone-implant interface. No osteolysis, loosening, or bone rarefaction was observed. At follow-up, two patients resumed sporting activities. One patient resumed skiing while the other resumed biking.

Our pilot study shows that TriboFit^® Buffer hip resurfacing arthroplasty is a valid alternative to MOMHR. Compared to the latter, the major advantage includes significantly lower metal wear generation, without any differences in the functional results. This new technology has the potential to expand the use of hip resurfacing to patients with renal malfunction, metal ion allergy/hypersensitivity and to fertile females.

Introduction: Ideal treatment of osteochondral lesions of the talus (OLT) is still controversial.

Aim of this study is to review the 10 years follow-up clinical and MRI results of open field Autologous Chondrocytes Implantation in the treatment of OLT.

Methods: From December 1997 to November 1999, 10 patients, age 25.8 +/−6.4 years, affected by OLT, received open field Autologous Chondrocytes Implantation. The mean size of the lesions was 3.1 cm² (2.2 – 4.3).

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.

Results: Before surgery the mean score was 37.9 +/−17.8 points, at 24 months it was 93.9 +/−8.5, while at final follow-up it was 92.7 +/−9.9 (p< 0.0005).

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.

Conclusions: The clinical and histological results have confirmed the validity of the technique utilized with a durability of the results over time. T2 mapping was adequate in detecting the quality of the regenerated tissue coherently with the bioptic results.

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.

Introduction: In situ subtalar arthrodesis cannot restore anatomical shape of the hindfoot in severe flat foot deformities. Purpose of this paper is to evaluate the result of 250 feet consecutively operated by subtalar arthrodesis with distraction and insertion of a mini structural bone block (SAMBB).

Material and Methods: 178 patients (250 feet), mean age 55+/−11 years affected by acquired adult flat foot with subtalar arthritis were evaluated clinically and radiographically and selected to receive SAMBB.

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.

Results: Before surgery the mean AOFAS score was 42+/−15, while it was 90+/−8 at follow-up (p< 0.005). Mean heel valgus deviation at rest was 15°+/−8° preoperatively and 6°+/−5° at follow-up (p< 0.005). Mean angulation of Meary’s line at talonavicular joint level was 160°+/−11° preoperatively and 174°+/−8 at follow-up. No complications were found. No or minimal arthritis progression was observed in the ipsilateral foot joints at follow up.

Conclusions: SAMBB resulted in an adequate correction of the deformity, with restoration of the anatomical shape of the hind foot and correction of the relationship with the midtarsal joint with no need of hardware. Consequent reduced arthritis progression and excellent clinical result were obtained.

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

Objective: Different

Methods: have been proposed to date to achieve the regeneration of hyaline cartilage in osteochondral lesions of the talus (OLT). The aim of this study was to present a new one-step arthroscopic procedure with the use of mesenchimal stem cells (MSC) supported on a collagen scaffold and Platelet Rich Fibrin (PRF).

Methods: 14 patients with a diagnosis of OLT underwent this procedure. The MSC were harvested from the posterior iliac crest and concentrated directly in the operating room. An ankle arthroscopy was performed with lesion detection and curettage. The cell concentrate was mixed with a collagen paste as scaffold and with PRF as a pool of growth factors in order to have a final composite to fill the lesion site. Partial weight bearing for 2 months and early ROM was advised postoperatively.

Results: According to the American Orthopaedic Foot and Ankle Score (AOFAS) system the patients had a preoperative score of 65.1 (range 35–79), a postoperative of 69.4 (range 61–97) at 6 months and of 83.6 (range 65–100) at 12 months follow up. MRI control at 6 and 12 months showed a progression of the reparative process in the osteochondral lesions. Histological and immuno-hystochemical analysis on a sample biopsed during a control arthroscopy at 12 months confirmed the hyaline quality of the regenerated cartilage.

Conclusions: This one-step technique demonstrated to be capable to regenerate hyaline cartilage, with the advantages of a reduced surgical time, lower costs and lower patient’s morbidity.

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.

Materials and Methods: Four hundred and thirty three consecutive female patients were included in our study. Inclusion criteria were: AO/OTA fracture type A1, A2 or B, age ? 80 years and minor trauma. BMD values of the lumbar spine (L2–L4) and right proximal femur (neck, trochanter, Ward’s triangle) were measured by dual-energy x-ray absorptiometry. Patients were divided into three groups: Group A had trochanteric fractures (n = 79, average age 85 ? 5), Group B had femoral neck fractures (n = 67, age 84 ? 4) and Group C had no fractures (n = 287, age 82 ? 2). Data was assessed statistically using Analysis of Variance (ANOVA) and receiver operating characteristic (ROC) analysis.

Results: Group A ROC curve had higher values when compared to Group B ROC curve in all corresponding BMD tested sites. Total number of patients with femoral neck fracture and a T-score higher then −2.5 SD were 14 (20.9%), 25 (37.3%) and 16 (23.9%) at the femoral neck, trochanter and at the Ward’s triangle respectively. Patients with a trochanteric fracture and a T-score higher than −2.5 SD were 8 (10.1%), 15 (19.0%) and 12 (15.2%) at the femoral neck, trochanter and Ward’s triangle respectively. BMD values at the trochanteric measurement site demonstrated that the incident rate between the two patient groups differed significantly depending on the diagnosis of osteoporosis (Chi square test: X² = 6.12, p = 0.013).

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.

Conclusions: There was a significant difference between non-osteoporotic related fractures in Group A and Group B. There were more non-osteoporotic related fractures in Group B. A lower BMD was found in patients with trochanteric fractures than in patients with femoral neck fractures. Assessment of bone quality in these patients is of paramount importance in choosing the correct surgical treatment. In patients with poor bone quality, fixation augmentation techniques can be used. We recommend routine DXA scans of the affected fractured hip in all elderly hip fracture patients prior to surgery.

Aims: This work analyzed the effects of storage by fresh-freezing at −80°C on the histological, structural and biomechanical properties of the human posterior tibial tendon (PTT), used for ACL reconstruction.

Methods: Twenty-two PTTs were harvested from eleven donors. For each donor one tendon was frozen at −80°C and thawed in physiologic solution at 37°C, and the other was tested without freezing (control). Transmission electron microscopy (TEM), differential scanning calorimetry (DSC) and biomechanical analysis were performed.

Results: We found the following mean changes in frozen-thawed tendons compared to controls: TEM showed an increase in the mean diameter of collagen fibrils and in fibril non-occupation mean ratio, while the mean number of fibrils decreased; DSC showed a decrease in mean denaturation temperature and denaturation enthalpy. Biomechanical analysis showed a decrease in ultimate load and ultimate stress, an increase in stiffness and a decrease in ultimate strain of tendons.

Conclusions: Fresh-freezing brings about significant changes in the biomechanical and structural properties of the human PTT. A high variability exists in the biophysical properties of tendons among individuals and in the effects of storage on tendons. Particular care is required when choosing an allograft tendon and further studies are required to clarify the role of donors’ age and sex, and other factors, in determining the suitability of an allogenic tendon. The future directions could be:

(a) To choose the tendon grafts considering the donors’ characters;

INTRODUCTION: Post-traumatic arthritis of the ankle in the young active patient represents a reconstructive challenge. Fresh total shell osteochondral allografts are an increasingly popular option in the reconstruction of various amounts of cartilage defects, although concerns for bipolar allografting are reported. The purpose of this study is to describe the preliminary results of a series of 18 bipolar shell ankle allografts performed by using a specifically designed instrumentation.

METHODS: 18 patients, 13 males and 5 females (mean age 31±10 years) affected by post traumatic arthritis of the unilateral ankle joint grade III received bipolar shell allograft of the ankle. The mean follow-up was 12 months (range 24–8). The ideal patient to allograft match was permitted through CT scan and x-rays. Two steps surgery, one for allograft preparing and one for the recipient site, were performed by using specifically designed jigs. Patients evaluation was carried out clinically by AOFAS and radiographically by X-Rays, CT scans, MRI.

RESULTS: No intraoperative, complications occurred. All the patients demonstrated good consolidation rates of the allograft at X-Rays, CT scan and MRI controls performed at 4, 6, 8, and 12 months. At 8 months follow-up, all the patients were allowed complete weight bearing. Normal ROM of the ankle and regular gait with no pain and no need of support was resumed in 13 patients. In 2 patients a fracture of the fibula was reported. In one case, cause of the fracture was patient non compliance to the weight-bearing restriction. In the other case the fracture occurred distal to the osteotomy site, possibly due to a trauma. Both the cases required revision of the graft which appeared damaged in the lateral site. In the first case an ankle arthrodesis was performed. A bioptic harvest of the transplanted cartilage in 5 patients at 1 year follow up demonstrated chondrocytes vitality > 90%.

DISCUSSION: Accurate preoperative planning, sizing, and the use of specifically designed jigs makes viable and reproducible the bipolar shell allograft in the ankle joint in selected cases. Although preliminary results are encouraging, longer follow-up is required in order to confirm longer term cartilage viability and the validity of the technique.

INTRODUCTION: Diaphyseal aseptic nonunions are challenging complications in forearm fractures, as length imbalance of radius and ulna impairs severely its function. The aim of this study is to report the results of a series of patients operated on by an original technique.

MATERIAL AND METHODS: 60 patients aged 17–72 years (mean 35) were treated between 1980 and 2000. Ten patients presented radius nonunion, 37 ulna non-union, and 13 nonunion of both bones. Nonunions occurred after conservative treatment in 8 cases, after one surgical procedure of plating or nailing in 47 cases and after 2 or more surgical procedures in 5 cases. Surgical treatment occurred at mean 36 months after the fracture and consisted of freshening the bone and applying a plate and an opposite cortical bone allograft; in 17 cases omologous intercalary bone graft was applied to restore length, axial and rotational alignment. Postoperative treatment consisted of functional bracing associated with intensive rehabilitation of the elbow and wrist beyond clinical and radiographic union. Average follow up was 15±7 years.

RESULTS:. One implant failed due to infection, requiring additional surgery. Mean elbow ROM was 122°±18. Compared with the contralateral arm, mean loss of wrist ROM was 20°±17. Mean loss of forearm rotation was 25°±15. Average healing time was 14±4 weeks X-ray analysis showed bone healing and good osteointegration of the graft in all cases.

DISCUSSION AND CONCLUSION: Combining a plate and an opposite massive cortical bone graft resulted to be a very effective technique for surgical treatment of forearm nonunions.

Purpose: To evaluate the safety and efficacy of hylan G-F 20 viscosupplementation in patients with symptomatic osteoarthritis (OA) of the ankle.

Methods: Prospective, multi-center, open study in patients with primary or secondary grade II talocrural OA confirmed by X-ray. At baseline, patients had to score between 50–90 mm on the Patient-completed Ankle OA Pain VAS (0–100 mm). Patients received one intra-articular injection of 2 ml of hylan G-F 20 and were given an option of a second and final 2 ml injection if their pain remained between 50-90 mm on the VAS after 1, 2 or 3 months. Intraarticular injections were placed in the anteromedial portal of the ankle joint as described for ankle arthroscopy. Patients were followed for 6 months after the final injection. As rescue medication, patients could only take paracetamol up to 4 g per day, except on the day of or the day before a study visit.

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).

Results: Fifty-five patients (33 M; 22 F) were enrolled and received a first injection of hylan G-F 20. Twenty-four patients (44%) received a second injection. The mean age was 41 years (range 19–70). Overall, treatment with hylan G-F 20 was well tolerated. Seventeen patients (31%) had a treatment related AE of the target ankle. All were of mild or moderate intensity, the majority consisting of arthralgia and injection site pain. There was a statistically significant decrease in Ankle OA Pain VAS score from 68.0 mm at Baseline to 33.8 mm at Month 3 (p< 0.001, paired t-test), which was maintained at 6 months follow-up. The decrease was statistically significant at all time points. Patients who received only 1 injection demonstrated a greater decrease at 3 months (−42.5 mm) than patients with 2 injections (−23.5 mm). The secondary efficacy endpoints showed similar results. Of the total study population, 29 patients (53%) were responders (i.e. at least a 50% decrease in ankle OA pain) after 3 months. 64% of patients receiving 1 injection were responders after 3 months. The SF-36 questionnaire showed statistically significant improvements for both the physical and mental component scores at 3 and 6 months follow-up.

Conclusions: Treatment of OA of the ankle with intraarticular hylan G-F 20 injections is well tolerated. Treatment with hylan G-F 20 significantly decreases pain which is maintained for up to 6 months.

OBJECTIVE OF THE STUDY: Metatarsal osteotomies are common procedures for correction of hallux valgus. The aim of this study is to compare linear distal metatarsal osteotomy (LDMO) with SCARF osteotomy a clinical prospective randomised study.

METHODS: Forty patients affected by bilateral hallux valgus similar in both sides regarding clinical and radiographic assessment were included. X-rays, AOFAS, Maryland Foot Score (MFS) were considered before surgery up to 4 years follow-up. All patients were operated bilaterally, and received SCARF osteotomy in one side, and in the other LDMO performed through a 1 cm skin incision under the direct view control. Duration of surgery was recorded. Postoperative care was similar in both groups and consisted of gauze bondage and weight bearing with talus shoes for 4 weeks.

RESULTS: No statistical differences were observed in preoperative HVA, IMA, PASA in both groups. Average surgical time was 17 minutes in SCARF and 3 minutes in LDMO (p< 0.0005). No complications were observed in the series, with no wound dehiscence. All osteotomies healed. At 4 year follow up, no statistical differences were observed in HVA, IMA, PASA comparing SCARF with LDMO. Average AOFAS score was 87±12 in SCARF and 89±10 in LDMO (p=0.07), and MFS was 86±7 in SCARF and 90±3 in SERI (p=0.08).

CONCLUSION: Both SCARF and LDMO techniques resulted effective in the correction of hallux valgus, however SERI, a minimally invasive technique, performed with a shorter skin incision, more rapid surgical time, fixed with a less expensive device (one kirshner wire), resulted in a better clinical outcome.

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.

INTRODUCTION Metal-on-metal hip resurfacing (MOMHR) has recently been reintroduced as a viable treatment option for young active patients. A short femoral neck and insufficient head are common deformities following CDH, Perthes disease and SFCE. Therefore, severity of these deformities is a contraindication for MOMHR, as contact between the femoral resurfacing component and the femoral head would be inadequate and off-set insufficient.

METHODS 32 patients with severe deformity of the hip were treated with Birmingham hip resurfacing and head lengthening. We used a standard acetabular component in 18 patients and a CDH acetabular component and supplementary screw fixation in 14. Bone chips produced while reaming the acetabulum were impacted on the femoral head to achieve the desired length, as evaluated on pre-op x-rays. Rehabilitation included no weight-bearing for 1 month and partial weight-bearing for another month.

RESULTS Median patient age was 44 years. Median head lengthening was 1.2 cm. Minimum follow-up was 3.1 years, maximum 5.2. Mean Harris Hip Score was 98. At follow-up 82% of the patients were involved in heavy or moderately heavy work. 34% of the patients practiced sports. Co and Cr serum concentrations at 25 months were respectively ng/ml 1.76, and 0.75. DXA analysis of the proximal femur showed complete recovery of BMD in Gruen zone 1 and increased in zone 7 (p= 0.05). There were no major complications.

DISCUSSION AND CONCLUSIONS The absence of major complications and the quality of our results support this technique in young active patients with severe deformity of the hip.

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.

INTRODUCTION: Distal metatarsal osteotomies have been described for surgical treatment of hallux valgus with good results. The aim of this study is to review the results of our first 1000 consecutive hallux valgus cases treated by minimally invasive distal metatarsal osteotomy, SERI (Simple Effective Rapid Inexpensive).

MATERIAL AND METHODS: 1000 feet in 641 patients (359 bilateral), aged between 20 and 65 years (mean 49) affected by hallux valgus without arthritis were studied. Inclusion criteria were deformity less than 40° and intermetatarsal angle up to 18°. A 1-cm medial incision at the metatarsal neck, and a complete osteotomy were performed using an oscillating saw. With the naked eye all characteristics of the deformity were corrected by displacement of the metatarsal head (HVA, IMA, PASA, dorsal or plantar displacement). The osteotomy was stabilized by a 2-mm Kirschner wire. Immediate weight bearing was allowed with gauze bandage and talus shoes for 4 weeks. All patients were checked at an average follow-up of 37 months.

RESULTS: All osteotomies healed, delayed consolidation was observed in 25 feet. Slight stiffness was observed in 31 feet. Mean AOFAS score was 48+15 pre-op and 89+13 at follow up. The pre-op HVA was 32+8, while at follow-up it was 18+8 (p< 0.005), pre-op IMA was 14+3, while at follow-up it was 6+4 (p< 0.005), the pre-op PASA was 21+9, while at follow-up was 9+8(p< 0.005).

DISCUSSION AND CONCLUSION: SERI osteotomy was simple, effective, rapid and inexpensive in correcting hallux valgus deformity. Clinical and radiographical findings showed an adequate correction of the deformity.

INTRODUCTION: This prospective randomized study investigated short-term outcomes of cemented vs. HA-coated hip arthroplasty in elderly osteoporotic patients with femoral neck fractures.

METHODS: Forty consecutive patients with femoral neck fractures (AO/OTA fracture type B2 and B3) were randomized to receive either an AHS prosthesis (Group A, n = 22, cemented implant) or a Furlong prosthesis (Group B, n = 18, HA-coated implant). Inclusion criteria were: female age ≥75, fracture resulting from minor trauma, ability to communicate and bone mineral density (BMD) T-score at the contralateral hip lower than −2.5 SD. Subjective assessment was evaluated according to a rating system 0-(unsatisfactory) to 10(satisfactory). Average follow-up was 29 months for Group A and 27 months for Group B.

RESULTS: Average patient age was 75 ± 5 in both groups. There were no differences in ASA scores between the two groups. Surgical time was 77 ± 12 minutes for Group A, and 72 ± 13 minutes for Group B (ns). Harris hip score was 46 ± 36 in Group A and 62 ± 33 in Group B. (p < 0.05). SF-36 was 35 ± 32 in Group A and 54 ± 32 in Group B (ns). Subjective assessment was 5 ± 4 in Group A and 7 ± 3 in Group B (ns). The incidence of death during the follow-up period was 33% in Group A and 15% in Group B. (p < 0.05). One Group A patient underwent revision due to implant loosening. A Furlong prosthesis was successfully implanted in this patient.

DISCUSSION: Although femoral neck fractures in elderly osteoporotic patients are usually treated with cemented arthroplasty, our comparative study showed better results with the Furlong prosthesis, even if statistical significance was reached in only two parameters. The outcomes obtained with the Furlong prosthesis are due to the ability of the HA-coating to bind with osteoporotic bone, thus establishing a stable fixation. Fixation failed in only one cemented implant, but our case number was limited and the follow-up short. Post-op mortality at the time of follow-up was high. This was not unexpected, given the age level and health status of the study groups. This study shows that the HA-coated Furlong prosthesis is a viable option for the treatment of elderly osteoporotic femoral neck fracture patients.

Introduction: Screw loosening is a common complication of osteoporotic fracture fixation leading to implant loosening, fracture malunion and non-union. Because recent animal studies have shown that bisphosphonates improve implant fixation we wanted to assess whether alendronate (ALN) improves screw fixation in a clinical setting of osteoporotic fractures.

Methods: Sixteen consecutive patients with AO/OTA A1 pertrochanteric fractures were selected. Inclusion criteria were: female over the age of 65, BMD T-score less than −2.5 SD. Fractures were fixed with a pertrochanteric fixator and 4 hydroxyapatite (HA)-coated screws. Two screws were implanted in the femoral head (screw positions 1 and 2) and two in the femoral diaphysis (screw positions 3 and 4). Patients were randomized to either postoperative systemic administration of ALN, 70 mg per week for 3 months (Group A) or no ALN. Fixators were removed at 3 months post-op in all patients.

Results: All the fractures healed. No differences in screw insertion torque between the two groups were found. No pin loosening or infection occurred. The combined mean extraction torque of the screws implanted at positions 1 and 2 (cancellous bone) was 3181 ± 1385 N/mm in Group A and 1890 ± 813 N/mm in Group B (p < 0.001). The combined mean extraction torque of the screws implanted at positions 3 and 4 (cortical bone) was 4327 ± 1720 N/mm in Group A and 3785 ± 1181 N/mm in Group B (ns).

Discussion and Conclusion: This is the first study to demonstrate in a clinical setting improved screw fixation following post-operative ALN treatment. We observed a two-fold fixation increase in the screws implanted in cancellous bone. With cortical bone, the difference in screw fixation was less marked. Besides its bone preserving ALN should be recommended as an effective solution to improve fixation in osteoporotic bone.

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.

INTRODUCTION: Displaced comminuted intra-articular calcaneal fractures (DCCF) need anatomic reduction to avoid painful subtalar joint, deformities, tendon or nerve impingment. Open reduction and internal fixation has been extensively reported, but all series reported considerable rate of skin complications, infections and need of additional plastic procedure. The aim of this study is to review a series of DCCF operated by minimally invasive technique.

MATERIAL AND METHODS: 66 DCCF type Sanders II-III were selected in 63 patients aged 18–57 years. X-ray and CT scan were performed. Surgery consisted of percutaneous traction-reduction of the calcaneal body by bone forceps and fixation by K-wires under image intensifier. Then, a lateral 3 cm skin incision was performed to reduce subtalar joint and to fix it by 1 or 2 screws. In case of involvement of the calcano-cuboid joint, the incision was distally extended and a 4-hole plate was applied. K-wires were removed 5 weeks after surgery and weight bearing was permitted 12–16 weeks after surgery. Patients were evaluated clinically by AOFAS score and radiographically at 4 years follow-up (3–7).

RESULTS: No skin complications or infections were encountered in the series. All fractures healed. Mean postoperative Bohler angle was 29±5°. AOFAS score was 89±11. 31 cases were excellent, 22 good, 9 fair and 4 poor. 25 cases presented radiographic signs of subtalar joint arthritis, painful only in 4.

DISCUSSION AND CONCLUSION: Minimally invasive surgical treatment resulted adequate for treating DCCF, in fact if soft tissues are preserved by surgical trauma, dangerous complications like infections and skin problems can be avoided.

Patellar maltracking after total knee arthroplasy (TKA) introduces complications such as anterior knee pain and patellar subluxation, generally due to prosthetic component malallignment in both tibiofemoral (TF) and patellofemoral joints. It is still debated if it is necessary to resurface the patella, which would better adapt the patellar articular surface to the prosthetic femoral troclea with a prosthesis, but also result in possible bone fractures. In this study, an in-vitro analysis is presented in order to identify differences between intact and TKA patellar tracking with and without patellar resurfacing and to show how much the latter is similar to intact knee patellar tracking.

Three fresh-frozen amputated legs with knees free from anatomical defects and with intact joint capsule, collaterals and quadriceps tendon were analyzed using the Stryker knee navigation system (Kalamazoo, MI-USA). Landmark digitations were used to define anatomical frames for femur, tibia and patella. Manually driven TF flexions, from 0 to 140, were performed under conditions of no load and of 10 kg on the quadriceps, with intact knee and TKA with patella resurfaced and not. TF flex/extension, intra/extra rotation, ad/abduction were calculated according to a standard convention. Patellar flex/extension, medial/lateral tilt, rotation and shift were calculated according to a recently proposed articular convention.

Since more repeatable, results relative to trials under 10 kg are reported. Intact knee: 4 abduction; considerable intra rotation (from 16 to 4), followed by continuous extra rotation starting at 30 TF flexion; linear increase in patellar flexion (from 20 to 110); initial medial patellar rotation (from 12 to 8), followed by medial rotation starting at 60 TF flexion; initial lateral patellar tilt (from 4 lateral to 4 medial), followed by medial tilt starting at 70 TF flexion; initial 6 mm lateral patellar shifts from 0 to 80 TF flexion, followed by 4 mm medial shift. TKA knee: small differences in ad/abduction between intact and TKA knees, both with and without resurfaced patella; slight initial extra rotation, followed by continuous intra rotation starting at 20 TF flexion; linear increase in the flexion of the patella, both resurfaced and not, close to the that of the intact knee; patellar rotation more lateral than in the intact knee; patellar tilt without resurfaced patella closer to the intact knee one; 6 mm lateral patellar shift, likely accounted for the surgical technique.

Slightly more than TKA with resurfaced patella, TKA with non resurfaced patella flexes nearly like the intact knee. The closeness in values of patellar flexion and tilt represents a proof of the closeness in behavior of not resurfaced patella in TKA to the patella in the intact knee.

Introduction: The main goal of surgical correction of hallux valgus is the morphological and functional rebalance of the first ray and correcting all the characteristics of the deformity. Historically, distal metatarsal osteotomies and SCARF have been indicated in cases of mild or moderate deformity with inter-metatarsal angles up to 20° and are procedures widely used for correction of hallux valgus. The aim of this study is to compare a distal metatarsal osteotomy recently described (SERI) with SCARF osteotomy in a clinical prospective randomised study.

Methods: 20 patients with bilateral hallux valgus similar on both sides regarding clinical and radiographic assessment were included. Clinical evaluation using American Orthopaedic Foot and Ankle Score (AOFAS) and radiographic assessment were considered before surgery up to 2 years follow-up. All patients were operated bilaterally in the same surgical sitting, and received at random SCARF osteotomy on one side, and on the other a SERI osteotomy performed through a 1 cm skin incision under tdirect view control and fixed with one Kirschner wire. Duration of surgery was recorded. Postoperative care was similar in both groups and consisted of gauze bandage and weight bearing with talus shoes for 30 days.

Results: No statistical differences were observed in preoperative HVA, IMA, DMAA in both groups. Average surgical time was 17 minutes in SCARF and 3 minutes in SERI (p< 0.0005). No complications were observed in the series, with no wound dehiscence. All osteotomies healed uneventfully. At 2 year follow up, no statistical differences were observed in HVA, IMA, DMAA comparing SCARF with SERI. Average AOFAS score was 87±12 in SCARF and 89±10 in SERI (p=0.07).

Conclusions: Both SCARF and SERI techniques proved effective in the correction of hallux valgus, however SERI, performed with a shorter skin incision, in less surgical time, fixed with a cheaper device (one Kirschner wire), resulted in a better clinical outcome.

Introduction: Facioscapulohumeral muscular dystrophy (FSHD) is the third most common hereditary disease of the muscle after Duchenne and myotonic dystrophy. FSHD consists in an atrophic myopathy with predominant involvement of the face, upper arms, and shoulder muscles. FSHD compromises the muscles of the scapu-lothoracic joint, and usually spares muscles of the scapu-lohumeral joint. Consequently, when the patient tries to abduct or foreword flex the shoulder, the contraction of the relatively preserved scapulo-humeral muscles produces an abnormal rotation of the scapula, that is not hold to the chest wall because of the insufficiency of the scapulo-thoracic muscles, resulting in a winged scapula and in a limited arm motion. The aim of this study is to describe an original scapulopexy and report the long term results obtained in 9 patients affected by FSHD.

Material and methods: Nine patients (4 male and 5 female) affected by winged scapula in FSHD were observed and selected. Average age at surgery was 25 years (range 13–39). Surgery consisted in scapulopexy of both sides in the same surgical time. Through a skin incision on its medial border the scapula was exposed and positioned over the chest. The 5th to the 8th ribs were exposed in the part below the scapula. The position of the scapula over the chest was fixed by 4 doubled metal wires to the 5th, 6th, 7th and 8th rib. Each wire was passed anteriorly to the rib, and into a hole performed 1.5 cm from the medial border of the scapula. By tightening the wires, the scapula was fixed firmly over the chest. A figure of eight dressing that holds the shoulders back was applied immediately after surgery and maintained for six weeks.

Results: The average surgical time was 65 minute for each single procedure. One patient experienced an unilateral pneumothorax the day after operation, which resolved spontaneously in 48 hours. Average follow up was 11 years (range 3–15). All patients experienced a complete resolution of the winged scapula and an improvement of range of motion of the shoulder compared to the pre operative conditions. Average pre-operative abduction was 68 and post-operative was 85. Average pre-operative flexion was 78 and post-operative 112.

Discussion: This technique is easy and quick to perform, does not require grafts, reduces post surgical complications such as pneumothorax or haemothorax, and ensures good results even at considerable follow-up.

Purpose: Four external fixation pin types differing in coating, design and implantation technique were tested in an animal study.

Methods: Forty tapered pins were divided into 4 Groups according to pin design type: Group A consisted of 10 standard self-tapping pins (ø5–6mm, pitch 1.75mm), Group B 10 hydroxyapatite (HA)-coated self-tapping (ø5–6mm, pitch 1.75mm), Group C 10 standard, self-drilling, self-tapping (ø5–6mm, pitch 1.25mm) and Group D 10 HA-coated, self-drilling, self-tapping (ø5–6mm, pitch 1.25mm). Four pins were randomly implanted into the femoral diaphysis of 10 sheep. The pins were implanted at 2-cm intervals apart. Pre-drilling was used for Groups A and B but not for Groups C and D. Sheep were euthanized 6 weeks after surgery.

Results: There were no major complications. Mean pin insertion torque was 3100 ± 915 Nmm in Group A, 2808 ± 852 Nmm in Group B, 2589 ± 852 Nmm in Group C and 2180 ± 652 Nmm in Group D. Mean pin extraction torque was 1570 ± 504 Nmm in Group A, 2128 ± 1159 Nmm in Group B, 1599 ± 809 Nmm in Group C and 2200 ± 914 Nmm in Group D. Insertion torque of the coated groups was lower than insertion torque of the standard groups (p < 0.05). However, extraction torque of Groups B and D was higher than Groups A and C (p < 0.05). No differences in pin fixation were found between the two coated pin groups (Group B and D). Morphologic analysis showed extensive bone to pin contact without fibrous tissue interposition in the coated pin groups and fibrous tissue interposition in the uncoated pin groups.

Conclusion/Significance: This study demonstrated that coating pins with hydroxyapatite is effective regardless of the pin design and the implantation technique.

Tibial component loosening continues to be the most common mode of TKA failure. A debate persists on the dependence of mobilisation of this component on the equilibrium between mechanical load transfer and counterbalancing bone resistance. The aim of the present work is to study the in-vivo kinematics of TKA and to relate it with the degree of posterior slope with which the tibial component was implanted for two prosthesis designs with congruent polyethylene insert.

Twenty-three patients with osteoarthritis of the knee had TKA using a cemented prosthesis (OPTETRAK, Exactech). A cruciate retaining (CR, 10 knees) or a posterior stabilized (PS, 13 knees) implant was randomly assigned at operation. Standard pre- and post-operative antero-posterior and lateral roentgenograms of the knee were taken. Fluoroscopic analysis was performed after at least 18 and 7 months after surgery for the CR and the PS group, respectively. Patients performed stair ascending, chair rising-sitting and step up-down motor tasks. Articular contacts were assumed as the two points on the medial and lateral femoral prosthetic condyles closest to the tibial component base-plate. The spine-cam distance was calculated as the minimum distance between corresponding surfaces.

Only small differences in the position of the contacts over knee flexion angles were found among the motor tasks and between the two TKA designs. An overall posterior location of the tibio-femoral contact points was found at the medial and lateral compartments over all motor tasks, a little more pronounced for the PS patients. Statistically significant correlation over the three motor tasks analysed was found between posterior position of the tibio-femoral medial contact in maximum knee flexion and the post-operative tibial posterior slope. This is true for the PS and for the aggregated groups. Although no statistically significant, a general trend is observed of higher degree of flexion at which the cam contacts the spine as the post-operative posterior slopes increases: a 35 higher knee flexion angle for a tibial component implanted with a 5 of posterior slope. Generally, even when the correlations were statistically significant the correlation coefficients were always lower than 0.4.

The present work reports combined measurements of post-operative posterior slope and full in-vivo relative motion of the components in both CR and PS TKAs. General trends were found between posterior slope of the tibial component and positions of the tibio-femoral contacts, but a statistically significant correlation was found only for the tibio-femoral medial contact in maximum knee flexion in the PS and in the aggregated. General trends were found between posterior slope of the tibial component and degree of flexion at which the cam starts to be in contact with the spine. The nearly standard antero-posterior translation of the tibio-femoral contacts can be bigger in flatter polyethylene inserts.

Introduction: Neck hyperextension (NH) is defined as a progressive increase of lordosis associated with a limitation in flexion of the cervical spine, which ultimately results in an inability to approximate the chin to the sternum. NH may occur in relation to several myopathies. It is characterized by a general weakness and contractures of the axial muscles which produces a progressive increase of lordosis associated with a limitation in flexion of the cervical spine, that forces the patient to assume awkward compensatory postures to maintain balance and level vision. This study reports on operative complications, the degree of correction, the achievement of a solid arthrodesis, the maintenance of the correction and the clinical assessment of 7 patients.

Material and methods: Seven patients affected by various myophaties and NH were included. The mean age was 16.5 years (10–28 years). All underwent surgery, in which the paravertebral muscles were detached from the spinous processes and then transversally sectioned in order to bilaterally expose the laminas of vertebrae C2 to C7. The space between C1–C2 appeared mobile, while the spinous processes from C2 to C7 were close together and thus allowed only a very limited motion in between them. Ligamenti interspinosus and nuchae were detached and the facet joints from C2 to C7 were enlarged by capsulotomy. With a spreader rongeur, the interspinous spaces at each level were gently opened. Cortical cancellous autologue graft were shaped into wedges. After careful opening of each interspinous space, the bone wedges were driven between the spinous processes to maintain the achieved correction. The average follow-up time was 10.4 years (2.4–16.5 years).

Results: No major surgical complications occurred. At follow-up, the average angle between C2–C7 in neutral position had decreased (p = 0.016) from 50.7 (40–70) to 21.4 (2–50). The range of motion in the C1–C2 joint remained unaffected, while it decreased in C2–C7 (p = 0.016) from 33.5 (15–64) to 1.8 (0–8). In all cases, a solid arthrodesis was achieved.

Discussion and conclusion: The follow-up showed significant clinical improvement of posture in all patients. Our study has shown surgical treatment of NH to be an effective method within the whole series of seven patients, achieving both good immediate and good long-term results.

Introduction Osteochondral lesions of the talus are a common occurrence especially in sports injuries. The biomechanical nature of the ankle joint makes it susceptible to sprains which can cause damage not only to the capsulo-ligamentous structures, but also to the joint cartilage and subchondral bone. As it is known, joint cartilage is a highly specialized and multitask tissue. Because joint cartilage has poor reparative capability, damage may be irreversible and as a consequence, can also lead to osteoarthritis. The purpose of this study is to review the results of a series of patients treated with autologous chondrocytes implantation (A.C.I.) and to describe the evolution in surgical technique that we have been implemented in the last 8 years.

Methods Thirty-nine patients with a mean age of 27 8 years affected by osteochondral lesions of the talus > 1.5 cm2, were treated by autologous chondrocyte implantation. All patients were checked clinically and by MRI up to 4 years follow-up. The first 9 patients received the ACI by open technique and the remaining 30, arthroscopically. In the last 10 patients the cartilage harvested from the detached osteochondral fragment was used for the colture. All patients were checked clinically (AOFAS score), radiographically and by MRI, before surgery, at 12 months and at follow-up. Eleven patients underwent a second arthroscopy with a bioptic cartilage harvest at 1 year follow-up. Samples were stained with Safranin-O and Alcian Blue. Immunohistochemical analysis for collagen type II was also performed

Results Before surgery the mean score was 48.4 17 points, at 12 months 90.9 12 (p< 0.0005), while at follow up was 93.8 8 (p< 0.0005) demonstrating an improvement over time. The histological and immunohistological analyses performed on the cartilage samples using Safranin-O, Alcian Blue staining and anti-human collagen type II antibody respectively showed a typical cartilage morphology, were positive for collagen type II and for proteoglycans expression.

Conclusions The clinical and histological results have confirmed the validity of the technique utilized, with laboratory data confirming the newly formed cartilage was of hyaline type for all the cases evaluated.

Introduction: Deterioration of bone-pin interface, causing pin loosening and infection, is a major cause of postoperative complications following external fixation. This paper presents the results obtained using hydroxyapatite (HA)-coated pins in various bone types, such as osteoporotic bone.

Materials And Methods; In an animal study comparing HA-coated and standard pins, pin insertion and extraction torque were measured. Subsequently, a clinical study compared insertion, extraction torque and pin-tract infection rate of standard and HA-coated pins implanted in healthy and osteoporotic bone.

Results: hi the animal study, mean final insertion torque was 4360±1050Nmm in the standard group and 3420 ± 676 Nmm in the HA-coated group. Mean extraction torque was 253 ± 175 Nmm in the standard group and 3360 ± 1260 Nmm in the HA-coated group (p = 0.002). In the clinical study on healthy bone, the mean insertion torque was 4130 ± 2160 Nmm in the standard group and 3440 ± 1930 Nmm in the HA-coated group (p = 0.03). The mean extraction torque was 1470 ± 1700 Nmm in the standard group and 5130 ± 2300 Nmm in the HA-coated group (p < 0.001). There were 33 pin-tract infections in the standard group and 20 pin-tract infections in the HA-coated group (p < 0.05, power 0.9). The standard pin group had a mean extraction torque of 730 (0–5500) Nmm in the infected pin-tracks and 2110 (0–7000) Nmm in the uninfected pin-tracts (p < 0.0001). The HA-coated group had a mean extraction torque of 5310 (1000–8000) Nmm in the infected pin-tracts and 5080 (0–8000) Nmm in the uninfected pin tracts (NS). In the clinical study on osteoporotic bone, mean final insertion torque was 461 ± 254 Nmm in the standard group and 331 ± 175Nmm in the HA-coated group (p = 0.01). Mean extraction torque was 191 ± 154 Nmm in the standard group and 600 ± 214 Nmm in the HA-coated group (p < 0.0005). Pin infection rate was greater in the standard group (p < 0.05).

Conclusion: There was no deterioration of the bone-pin interface strength (measured by torque resistance at the time of pin extraction) with HA-coated pins. The improved strength of fixation of the HA-coated pins was associated with a lower incidence of pin-tract infection.