Several in vitro and in vivo studies have found correspondence between transepicondylar axis (TEA) and functional flexion axis (FFA) in healthy subjects. In addition some studies suggest that the use of FFA for rotational alignment of femoral implant may be more accurate than TEA. Ostheoarthritis (OA) may modify limb alignment and therefore flexion axis, introducing a bias at different flexion ranges during kinematic acquisition. In this study we want to understand whether OA affects somehow the FFA evaluation compared to TEA and whether the FFA could be considered a usable reference for implant positioning for osteoarthritic knees We included a group of 111 patients undergoing TKA. With a navigation system, we recorded intraoperative kinematic data in three different ranges of motion (0°-120°; 35°-80°; 35°-120°). We compared the difference in orientation of FFA (computed with the mean helical axis method) in the three ranges as also the difference with the TEA on frontal and axial planes. The correlation of preoperative limb deformity with FFA and TEA was also performed.Introduction
Methods
Patellar stability is an important component for a correct kinematic behaviour of the knee that depends on several factors such as joint geometry, muscles strength and soft tissues actions. Patellofemoral (PF) maltracking can results in many joint disorders which can cause pain and mobility alterations. The medial patellofemoral ligament (MPFL) is an important stabilizing structure for the patellofemoral joint. The aim of this study was to analyze patellofemoral kinematics with particular attention to the contribution of MPFL on patella stability. Using a navigation system PF kinematics during passive flexion/extension movements with quadriceps loaded at 60N, was recorded on 6 cadavers in three different anatomical conditions: intact knee, MPFL cut and MPFL reconstructed with graft. Test on patella was conducted without lateral force and with applied lateral force (25N). Tilt and lateral shift was evaluated in both cases at 0°. 30°, 60°and 90° of flexion.Introduction
Methods
We hypothesized that patients receiving a medial collagen meniscus implant (MCMI) would show better clinical, radiograpich and Magnetic Resonanace Imaging (MRI) outcomes than patients treated with partial medial meniscectomy (PMM) at minimum 10 year FU. Thirty-three non-randomized patients (males, mean age 40 years) were enrolled in the study to receive a MCMI (17 patients) or as control treated with a PMM (16 patients). All of them were clinically evaluated at time zero, 5 and minimum 10 years after surgery (mean FU 133 months, range 120–145) by Lysholm, VAS for pain, objective IKDC knee form and Tegner activity level. SF-36 score was performed pre-operatively and at final FU. Bilateral weight-bearing XRays were executed at time zero and at final FU. Minimum 10 years FU MRI images were compared with collected pre-operative MRI images by means of Yulish score. Genovese score was also used to evalute MCMI MRI survivorship.Purpouse
Material and Methods
Osteochondral defects are still a challenge for the orthopaedic surgeon, since most of the current surgical techniques lead to fibrocartilage formation and poor subchondral regeneration, often associated to joint stiffness and/or pain. Thinking of the ideal osteochondral graft from both the surgical an commercial point of view, it should be an off-the-shelf product; this is the research direction and the explanation for the new biomaterials recently proposed to repair osteochondral defect inducing an “in situ” cartilage regeneration starting from the time of the implantation into the defect site. For the clinical pilot study we performed, a newly developed nanostructured biomimetic scaffold was used to treat chondral and osteochondral lesions of the knee; its safety and manageability, as much as the surgical procedure reproducibility and the clinical outcome, were evaluated in order to test its intrinsic potential without any cells colture aid. A new osteochondral scaffold was obtained by enucleating equine collagen type 1 fibrils with hydroxyapatite nanoparticles in 3 different layers with 3 different gradient ratios at physiological conditions. 30 patients (9F, 21M, mean age 29,3yy) affected by either chondral or osteochondral lesions of the knee (8 medial femoral condyles, 5 lateral femoral condyles, 12 patellae, 8 femoral throcleas) underwent the scaffold implantation from January to July 2007. The sizes of the lesions were in between 2 and 6 squared cm. All patients and their clinical outcome were analyzed prospectively at 6, 12, 24 and 36 months using the Cartilage standard Evaluation Form as proposed by ICRS and an high resolution MRI.INTRODUCTION
MATERIALS AND METHODS
The menisci play a fundamental biomechanical role in the knee and also help in the maintaining of the articular homeostasis; thus, either a lesion or the complete absence of the menisci can invalidate the physiological function of the knee causing important damages, even at long term. Unfortunately, meniscal tears are often found during the ordinary orthopaedic practice while the regenerative potential of this kind of tissue is very low and limited to its peripheral-vascularized part; this is why the majority of these common arthroscopic findings are not reparable and often the surgeon is almost forced to perform a partial, subtotal or even total meniscectomy, regardless of the well-known consequences of this kind of surgery. Recently a porous, biodegradable scaffold made of an aliphatic polyurethane (Actifit(tm),Orteq Ltd) has been developed for the arthroscopic treatment of partial and irreparable meniscal tears; thanks to its particular structure, this scaffold facilitates the regeneration of the removed meniscal part, preventing the potential cartilage damage due to its complete or partial lack. We performed a prospective clinical study on 17 patients affected by a massive loss of meniscal substance either medial or lateral associated with intraarticular or global knee pain and/or swelling. We analyzed the patient both clinically and by using the International Knee Document Committee's (IKDC) Subjective and Objective Knee Evaluation Form. We also assessed the sport activity resumption by comparing the Tegner score at the time of the very first visit with the presurgery and prelesional ones. Finally, we also organized a control MRI at 6 and 12 months after surgery.INTRODUCTION
MATERIALS AND METHODS
We have shown in a previous study that patients with combined lesions of the anterior cruciate (ACL) and medial collateral ligaments (MCL) had similar anteroposterior (AP) but greater valgus laxity at 30° after reconstruction of the ACL when compared with patients who had undergone reconstruction of an isolated ACL injury. The present study investigated the same cohort of patients after a minimum of three years to evaluate whether the residual valgus laxity led to a poorer clinical outcome. Each patient had undergone an arthroscopic double-bundle ACL reconstruction using a semitendinosus-gracilis graft. In the combined ACL/MCL injury group, the grade II medial collateral ligament injury was not treated. At follow-up, AP laxity was measured using a KT-2000 arthrometer, while valgus laxity was evaluated with Telos valgus stress radiographs and compared with the uninjured knee. We evaluated clinical outcome scores, muscle girth and time to return to activities for the two groups. Valgus stress radiographs showed statistically significant greater mean medial joint opening in the reconstructed compared with the uninjured knees (1.7 mm (
Traumatic anterior shoulder dislocation and sub-luxation are common injuries. But few studies have compared arthroscopic and open stabilization of the shoulder at long-term follow up. The purpose of our study is to show whether an arthroscopic approach to repair Bankart lesion can obtain the same results at long follow up as an open procedure. We analyzed 110 non-randomized consecutive shoulders in 110 patients who underwent a surgical repair of recurrent anterior shoulder instability between 1990 and 1999. Eighty-two patients were available at long term follow up (74,5% retrieval rate). In particular, 49 patients (59.8%) (group A) were treated with arthroscopic transglenoid suture (modified Caspari) between 1990 and 1995 (mean 15,7 year FU), whereas, 33 patients (40.2%) (group B) were treated with open repair between 1995 and 1999 (mean 12,7 year FU). We evaluated the patients in terms of failure rates, Rowe and UCLA scores. The failure cases in the forty-nine patients treated with arthroscopic suture were 13, six dislocations and seven subluxations. The group A had also a Rowe score: function 24.2+8.2, stability 42.4+13.9, range of movement 18.6+3.8, total score 85.0+22.46. The UCLA score was: pain 8.8+1.7, function 8.6+2.1, muscle power 9.2+1.6, total score 26.4+4.8. Of the thirty-three patients treated with open repair, three had at least one post-op dislocations and four felt sometimes subluxations. The Rowe score in group B was: function 23.6+9.7, stability 41.2+14.9, range of movement 18.3+3.9, total score 83.2+24.4. Moreover the UCLA score was: pain 8.8+1.9, function 8.8+1.9, muscle power 9.2+1.2, total score 26.9+4.2. We showed that both techniques were fairly good in treatment of shoulder instability. In our series no significant difference was observed in redislocation rate and in Rowe and UCLA scores between the two groups. The recurrence rate (subluxations and dislocations) was high in both groups: the arthroscopic group had 26.5% and the open one had 21.2%. Our recurrence rate following open repair was higher than in many studies, while the rate after arthroscopic transglenoid procedure was almost equivalent. We hypothesize that one of the reasons for these higher recurrence rates may be the long term follow up. Another cause could be our decision to include subluxation as a failure value, even if there is no agreement about. In fact we believe it to be an important disability factor in sport as in life activities. After surgery, most of the patients returned to their preinjuried activities. But at long term follow up almost all patients have stopped high level sport activity. Moreover, at this long term follow up, some patients told us a feeling of muscle weakness in the last years. In conclusion patients had good impressions about their shoulders thanks to surgery, but also because of lower functional demand.
We performed a clinical, instrumental and radiographic study on a highly homogeneous series of 100 consecutive patients with unilateral ACL lesion at 7 years of minimum follow up, alternatively assigned to a single bundle reconstruction using patellar tendon (PT) or to a double bundle reconstruction using hamstrings (DB). Mean Tegner score was 4,8 for PT and 6,5 for DB (p=0,0005). Time for sport resumption was 6,6 months for PT and 3,8 months for DB (p=0,0052). There were no significative differences between the two groups regarding range of motion and functional subjective self-evaluation. Mean anterior displacement at instrumental evaluation performed with KT2000 showed no significative differences between the two groups. Objective clinical evaluation with IKDC was superior for DB group (A=86,5%; B=13,5%) respect to PT group (A=18,7%; B=75%; C=6,3%) (p<
0,0001). We found no differences regarding anterior knee pain between and Ahlback radiographic score the two groups and we have observed no recurrence of instability after surgical treatment. Double bundle ACL reconstruction with hamstrings has showed higher results respect to single bundle ACL reconstruction with patellar tendon in terms of Tegner score, IKDC, time for sport resumption.
We performed a retrospective clinical and radiographic evaluation of 100 cases operated in our institute between February 1996 and March 2003 with a mean follow-up of 60 months to assess the efficiency of UKR performed with a new minimally invasive technique. The aim of this study is to correlate the clinical outcome of the patients with the pre- and post-op alignment, and with implant positioning on coronal and sagittal plane. 100 patients (23 ♂, 64 ♀) underwent cemented UKR (De Puy Preservation Uni with all poly tibial component), both for arthritis and osteonecrosis. At the pre-op clinical and radiographic evaluation, 82 patients presented a varus deformity, 5 patients a valgus deformity. The Hospital for Special Surgery Score (HSS) was used to determine the subjective and objective clinical status of the patients before and after the intervention. Pre-op antero-posterior (AP) x-rays of the knee were executed to establish the femoro-tibial angle (FTA) and the angle between the affected tibial plateau and the tibial anatomical axis (PTA), while latero-lateral (LL) x-rays were performed to determine the posterior tibial slope (PS). To analyze ligamentous balancing, x-rays were performed both in supine and in plain weight bearing stance. Post-op, we performed supine AP e LL X-rays and at a mean follow-up of sixty months (12–84 months) we performed AP and LL plain weight bearing x-rays. We considered a knee with FTA >
175° as varus knee, 170°<
FTA<
175° as normal knee and an FTA <
170° as valgus knee. Moreover, we assumed a TPA >
90° for valgus knee and a TPA<
90° for varus knee. According with HSS scoring system, at a mean follow-up of 60 months, 63 (76%) cases were excellent (100-85 points), 15 (18%) cases were good (84-70 points), 5 (6%) bad results (<
60 points). Our results demonstrate that patients with a pre-operative varus alignment of 7 degrees are slightly more likely to be selected for UKR. In our series, patients with an excellent clinical result presented pre-operatively a mean varus deformity of 7,9°. According to literature, we demonstrated that a small amount of undercorrection with a residual varus deformity of 3–5° is the goal to be reached in order to avoid both rapid degeneration of the non-replaced compartment as well as the premature loosening of the replaced compartment. We performed a mean axial correction of 5,1° leaving a mean axial varus deformity of 2,8° in the excellent group. In our series the group with excellent results also showed a post-operative PTS of 7,1°, while mean pre-operative PTS was 6,6°. Moreover, the further our radiographic findings were from the optimal position suggested, the worst were the results : a decrease was evident comparing excellent group with good group and this was even more marked comparing excellent group with bad results group.
Arthroscopic selective resurfacing of the knee may be considered a treatment option for selected patients with focal articular damage. From more than 2 years in IX Division of Rizzoli Orthopaedics Institute(Bologna- Italy) we use, in selected cases with only one articular compartment damaged, an innovative resurfacing prosthesis. We mad a new design of focal resurfacing (MAIOR) that is possible to implant with arthroscopic technique and that realize both mini-invasive and mini-traumatic surgery. The fixation method of the MAIOR allows higher osteointegration by biomaterials and hydrossiapatite of new generation that permit a press-fit fixation of the implant. The new philosophy of this implant consist of early focal treatment with low compromise of bone. Many surgeons, in case of focal articular damage, prefer to attend to made an unique definitive surgical operation when the degenerative changes are more severe. This new implant permit to substitute, also in arthroscopic technique, only the articular damage and to avoid to attend a more important and diffuse articualr damage. It is an uncemented, focal resurfacing prosthesis that requires minimal bone sacrifice and utilizes a minimal invasive surgical (MIS) approach with or without arthroscopic assistance. In a prospective and consecutive study, 78 patients were followed up at least for 12 months. Subjective pain and joint function were assessed using Visual analogue scale (VAS) and Knee society scores respectively. The preliminary results are interesting and encouraging with subjective evaluation equal to 85% of normal knee. Significant reduction of pain and improvement in joint function was observed. Although, long term study will determine the real performance of the prosthesis, trend seems to be positive.
Information on knee kinematics during surgery is currently lacking. The aim of this study is to describe intra-operative kinematics evaluations during uni-compartmental knee arthroplasty (UKA) and total knee arthroplasty (TKA) by mean of a navigation system. Anatomical and kinematic data were acquired by Kin-Nav navigation system and analysed by a dedicated elaboration software developed at our laboratory. The study was conducted on 20 patients: 10 patients undergoing mini-invasive UKA and 10 patients undergoing posterior-substituting-rotating-platform TKA. In both group of patients the surgeon performed passive knee flexion immediately before and immediately after the prosthetic implant. Pattern and amount of internal/external tibial rotation in function of flexion were computed and significant changes between before and after implant were evaluated adopting Student’s t-test (significant level p=0.05). UKA implant did not significantly change the pattern of internal/external tibial rotation, nor the total magnitude of tibial rotation (15.75°±7.27°) during range of flexion (10°–110°), compared to pre-operative values (17.87°±7.34°, p=0.25). Magnitude of tibial rotation in TKA group before surgery (8.00°±3.67°) was significantly less compared to UKA patients and did not changed significantly after implant (5.96°±4.88°, p=0.09). Pattern of rotation before and after TKA implant were different between each other and between pattern in UKA patients both before and after implant. Intra-operative evaluations on tibial rotation during knee flexion confirmed some assumptions on knee implants from post-operative methods and suggest a more extensive use of surgical navigation systems for kinematic studies.
Total knee arthroplasty (TKA) is actually a satisfactory technique to reduce pain and enhance mobility in osteoartritic pathologies (OA) of the knee. However, life of the implant is strictly dependent on restoration of correct knee kinematics, as alteration of motion pattern could led to abnormal wear in prosthetic components and also damage soft tissues. The aim of our study was to evaluate new kinematic tests to be performed during surgery in order to improve the standard intra-operative evaluation of the outcome on the individual case. We used Kin-Nav navigation system to acquire anatomic and kinematic data, which were analysed by a dedicated elaboration software developed at our laboratory. Ten patients undergoing rotating platform cruciate substituting TKA were considered for this study. Immediately before the implant and immediately after component positioning, the surgeon performed 3 complete knee flexion imposing internal tibial rotation (IPROM) and 3 complete knee flexion imposing external tibial rotation (EPROM). Tibial rotation during IPROM and EPROM tests was plotted in function of flexion (in the range 10°–110°). Repeatability of IPROM and EPROM was tested by calculating ICC (Intra-class Correlation Coefficient) between 3 repeated curves. Distance between IPROM curve and EPROM curve was computed at various degree of flexion. Maximum distance obtained during all range of flexion before and after the implant were compared by Student’s t-test (significant level p=0.05). ICC for repeated motions were 0.99 for IPROM and 0.98 for EPROM. Maximum distance between tibial rotation in IPROM and EPROM was 27.82±6.98 before implant and significantly increased (p=0.001) to 40.09±6.92 after TKA. In one case we observed that the value remained similar before and after implant (from 33.11 to 33.98) while in one case we observed very large increase of rotation (from 30.56 to 50.01). The proposed kinematic tests were able to quantify the increase of tibial rotation after TKA implant. Future development of the study are encouraging and will include a larger sample and reflections on individual findings.
Samples prepared with Karnowsky fixing and urani-lacetate solution. Fibril diameter and transversal area measured by LEICA QUIN in 5 cuts randomly selected for each sample.
Investigation based on: Sport activity recover; IKDC; KT2000; isokinetical tests; muscular throphysm recover; Tegner and Lyshom score; Activity Rating Scale (ARS); Psychovitality Questionnaire; radio graphical evaluation in AP, LL and Rosemberg.
DB technique allows a faster sport activity and muscular throphysm recover and better results in the isoci-netical tests.