The treatment of medial knee osteoarthritis (OA) in conjunction with anterior knee laxity is an issue of debate. Current treatment options include knee joint distraction, unicompartmental knee replacement (UKR) or high tibial osteotomy with anterior cruciate ligament (ACL) reconstruction or total knee replacement. Bone-conserving options are preferred for younger and active patients with intact lateral and patello-femoral compartment. However, still limited experience exists in the field of combining medial UKR and ACL reconstruction

The aim of this study is to retrospectively evaluate the results of combined fixed-bearing UKR and ACL reconstruction, specifically with regard to patient satisfaction, activity level, and postoperative functional outcomes.

The hypothesis was that this represents a safe and viable procedure leading to improved stability and functional outcome in patients affected by isolated unicompartmental OA and concomitant ACL deficiency.

Fourteen patients with ACL deficiency and concomitant medial compartment symptomatic osteoarthritis were treated from 2006 to 2010. Twelve of them were followed up for an average time of 7.8 year (range 6–10 years). Assessment included Knee Osteoarthritis Outcome Score (KOOS), Oxford Knee score (OKS), American Knee Society scores (AKSS), WOMAC index of osteoarthritis, Tegner activity level, objective examination including instrumented laxity test with KT-1000 arthrometer and standard X-rays. Wilcoxon test was utilized to compare the pre-operative and follow-up status. Differences with a p value <0.05 were considered statistically significant.

KOOS score, OKS, WOMAC index and the AKSS improved significantly at follow-up (p < 0.05). There was no clinical evidence of instability in any of the knees as evaluated with clinical an instrumented laxity testing (p < 0.05). No pathologic radiolucent lines were observed around the components. In one patient a total knee prosthesis was implanted due to the progression of signs of osteoarthritis in the lateral compartment 3 years after primary surgery.

UKR combined with ACL reconstruction is a valid therapeutic option for young and active patients with a primary ACL injury who develop secondary OA and confirms subjective and objective clinical improvement up to 8 years after surgery.

The options for treatment of the young active patient with isolated symptomatic osteoarthritis of the medial compartment and pre-existing deficiency of the anterior cruciate ligament are limited. The indications for the unicompartimental knee prosthesis are selective. Misalignment femoral-tibia, varo-valgus angle more than 7°, over-weight, and knee instability were considered to be a contraindication.

The potential longevity of the implant and levels of activity of the patient may preclude total knee replacement, and tibial osteotomy and unicompartmental knee arthroplasty are unreliable because of the ligamentous instability.

Therefore, we combined reconstruction of the anterior cruciate ligament first and unicompartmental arthroplasty of the knee.

We included in this study six patients, three males and three female, mean age 53.6 years, that presented only osteoarthritis of medial femoral condyle and ACL deficiency.

In the first group included 2 patients, we performed arthroscopy ACL reconstruction with hamstring and unicompartimental knee prosthesis one-step, and in the second group included 4 patients, we performed the same surgical procedure in two-step.

The clinical and radiological data at a minimum of 1.5 years at follow-up. We evaluated all patients with KOOS score, and IKDC score.

At the last follow-up, no patient had radiological evidence of component loosening, no infection, no knee remainder instability. The subjective and objective outcome assessed with the scale documented satisfactory average results, both in patients of first group and in those of second group.

ACL deficiency induced knee osteoarthritis for incorrect knee biomechanics, and all patients could be submit a total knee replacement.

What method for preventing it? This combined surgical treatment seems to be a viable treatment option for young active patients with symptomatic arthritis of the medial compartment, in whom the anterior cruciate ligament has been ruptured.

Future developments and more data are necessary for standardised surgical approach.

Since 1989 more than 5000 Zweymuller stems have been implanted in the Orthopaedic Institute G. Pini, Milan, Italy. This uncemented stem which has been produced since 1979 nowadays is though to be one of the best prothesical solutions and this can be affirmed both on the easy operative techniques and on the bases of our clinical studies of follow up. This is also the most used uncemented coxofemural system in Europe. The advantages in the Zweymuller design are due to the rotatory stability and the slight volume of the implant, which in the international literature are referred as the key points of this success. The bone anchorage and the distribution of the weights is achieved both proximally and distally thanks to the conical stem, which in the proximal region is anchored on one side by the great wing of the trocanteris on the other side by the wedge effect.

In the distant cortical instead the borders of the stem get wedged in the bone. This very wide anchorage allows a great stability reflected also by the lack of weigh pain at diafisys level.

The same stem is used both for first implant as well as revisions (after evaluation of the bone stock, achieved in our studies by dexa) but also for intertrocanteric osteotomies.

The chance of a rapid mobilization of the patient makes this stem convenient also in geriatric orthopaedic cases. The material is a alloy of Ti, Al and Nb: this material has been studied directly for medical appliances and not only it doesn’t contain toxic or allergenic components but provide an high resistence to breaks. Osteointegration is favoured by the rough surfaces.

In our last clinical study on the follow up of patients treated with this kind of implant in the last 18 months we have seen a difference in those cases in which a pneumatic driver for nailing had been used in the operative room. Not only the operative time for the positioning has been reduced of one third but the implant resulted to be more precise.

The use of this driver allows a better fitting of the stem to the femural shaft as the cut is more precise. In fact the surgeon has a controlled magnitude and direction of the driving force and this force is anyway limited.

There is a remarkable reduction of cases of intra operative fractures. So we have collected datas on 70 randomized patients in whom this device had been used compared to the same number of patients operated without this apparel: the operative time is reduced of 15 minutes in average and as a consequence the risk of fat emboly has diminished; revisions for malpositioning and intraoperative fractures are almost worthless. Moreover the blood loss has reduced of 100 cc. This are only partial datas but seem to suggest that this device can provide a great help to the orthopaedic surgeon in the operative room as well as reducing complicances in patients: we plan that this driver together with the Zweymuller stem will represent in the future one of the most safe solution in the total hip replacement when the surgeon puts the indication for an uncemented implant.

In this work we mean explain our clinical experience about the use of a T.R.K. mobile meniscal bearing implanted during the 2000 and 2001 in our institute. The prostheses design allows the motion of the polietilenic component 5mm in the anteroposterior directions and 12.5 degrees in the internal and external rotation.

In association with the shaping of the femural contact surfaces this design allows a huge upgrade of contact surfaces compared with other protheses already in use. We have evaluated 17 patients on short term follow up, patients operated in our division, four males and 13 females. The average ages are 68 ± 8.

The indication was in all cases gonartrosis. The evaluation protocol includes:

§ Pre and post operative x rays (after 60 days);

§ Clinical evaluation of the range of motion;

§ D.E.X.A. mineralometry;

§ Stabilometric evaluation pre operative and after 6 months.

The first results have pointed out the disappearing of pain in all the patients, an optimal recovering of the articular function with no loss of extension, a good prothesic osteointegration (even in an initial phase in our cases) and the stabilometric evaluation confirms a soon proprioceptivity recovering and the motion of the operated limb.

After all this encouraging results we have decided to continue implanting this kind of protheses as we think that not only it warrants a better range of motion, but the utmost null polietilenic debris may allows a longer life to the implant as a consequence of the reduced stress rate.

The great diffusion of total hip replacement in young patients has generated as a consequence an increasing in the number of prothesic failing associated with more or less extended bone loss. We mean analyze the various surgical solution to this problem. In the planning of the best surgical treatment the evaluation of the degree of osteolysis is the more correct technique; in fact we have supported the classical radiological exams with the miralometry as DEXA (supplying quantitative data on the periprotesic bone stock). Data obtained in this way allow choosing more carefully the best protheses in the preoperative planning: mid or long stem, with or without bone graft, with or without materials which may promote a bone rehabilitation. Anyway the surgeon should have all the possible protheses solutions as it happens to change the operative plan during the operation. These are the criterion of choice of the revision protheses, keepin’ in consideration data acquired by D.E.X.A.:

GIR 1 (loosening and or widing of the femural shaft with reducing of the cortical without interruption of walls): If the mobilized protheses is uncemented and DEXA supplies datas about a good bone stock we try to use a first implant uncemented protheses

Kotz’s design, on the bases of follow up studies, seem to support Wagner’s theories about the distant anchorage: There is an attempt of periprothesic corticalization even though the huge bone loss. In the last years we have performed a revision modular distally anatomic stem characterized by a metafi sarial leaning on the proximal component.

The weight bearing is progressive on the base of the radiological evolution and DEXA as well. The complete bearing will be allowed only after a sufficient bone restoration.

In our experience uncemented protheses in the stem revision can allow in mid and long term good results expecially keeping in consideration that these patients had already coxofemural problems. The range of motion is difficulty improvable so the results must be weighted on the bases of the previous clinical situation. If patients are monitored in order to operate as soon as possible in case of mobilization, the use of uncemented protheses can be a valid way for the functional recovering of these patients.

The pre operative evaluation of the degree of osteolisys in cotyle revision in a prothesis is very important in order to plan the best surgical treatment.

In these cases above the traditional radiological and scintigrafic exams we have achieved a evaluation techniques bases on D.E.X.A. This technique allows obtaining data on the periprotheses bone stock. These are the criterion of choice of the revision protheses, keepin’ in consideration data acquired by D.E.X.A.:

GIR 1 (loosening and acetabular widing with persistence of walls). If the cotyle is uncemented and the biological age of the patient allows, we use to treat with a first implant press fit uncemented cotyle.

Conclusions: As a conclusion we can maintain that these indication may supply satisfactory datas thanks to the deep pre operative evaluation by DEXA. We have to keep in consideration that this pathology must be considered urgent: as soon as the operation is achieved the better bone stock will be available to the surgeon. The use of many kind of uncemented cotyle allows us, today more than ever, to restore the correct center of rotation without the risk of further mobilizations.

The actual data about prevalence of knee osteoarthritis, the concurrent increasing of mean age and therefore the high social costs for the care of this pathology, make particularly important to do the correct choice in knee artroprosthesis. In this work we mean compare three different type of knee prostheses implanted in our institute. We have evaluated 120 patients (98 females, 22 males) treated with TKR in I° Orthopaedic Division of Istituto Ortopedico “Gaetano Pini” – Milano. All patients were affected by primary knee osteoarthritis of high degree and 3 groups were made due to the type of prosthesis implanted.

Our evaluation protocol includes: 1. Local objective examination and evaluation of Range of Motion (R.O.M.); 2. Subjective functional questionnaire (Lequesne Index modified for knee osteoarthritis); 3. Stabilometric evaluation for Proprioceptive knee structures (KAT-2000 Breg Inc. USA); 4. Standard X-Ray, both in AP and lateral planes, with patient in standing position.

The X-Ray controls showed no early mobilisations or malfitting of all implants. In consideration of the short follow-up period we have to do a continuous monitoring for at least 5 years to express a definitive evaluation of implant stability; significatively better results regarding the post-op R.O.M. and subjective results with Lequesne Index have been obtained with the use of mobile plate prosthesis.

The first results have pointed out better results in the use of a fully mobile plate prosthesis, compared with the other results using rotating and fixed plate prostheses.

In our opinion this is obtained through the research of a better reproduction of human anatomy and trying to respect the common kinematics of knee, which has to be the future objective in design and technical development of knee arthroplasty.