This study identifies parameters that allow to foresee the necessity of soft tissue release (STR) before surgery. Femoral and tibial morphotype were defined evaluating several radiological parameters. Intra-operative STR during surgery was correlated to radiographic parameters identified. 33 cases were analysed and divided in 2 groups, release (6) no release (27), statistical evaluation has been performed using Mann-Whitney test and contingency tables for most relevant parameters. Three parameters were measured on femur and four on tibia.

The results confirmed the usability of angle between femoral anatomical axis and transepicondylar axis ATA (p< 0.001) and between femoral mechanical axis and tangent to distal condyles MCA (p< 0.001 ) as predictors, among tibial parameters angle between mechanical axis and tangent to tibial plateaux gives good results (p=0.028).The use of contingency tables highlighted that the combined use of ATA and MCA, gives better specificity than the use of a single angle.

Large bone defect repair has always presented a difficult treatment problem. Marrow-derived osteogenic progenitor cells combined with hydroxyapatite (HA) were used for segmental bone reconstruction. The validity of this model has been shown for the repair of bone defects of critical size in large animal models. We used this cell-based therapeutic approach to treat three patients with large bone defects.

The patients were 41, 22 and 16 years old and had large tibial, ulnar and humeral diaphyseal gaps that ranged in size from 3.0 to 28.3 cm³. Marrow samples were harvested from the iliac crest and osteogenic progenitors isolated and expanded “ex vivo”. The expanded cells were then combined with a highly macroporous bioceramic scaffold whose size and shape reflected each individual bony defect. The cell/bioceramic composites were implanted at the lesion sites. External fixation was used to stabilise the grafts.

At present all patients have been followed up for 4–5 years. Already after the first month after surgery an initial integration at the bone/implant interface was evident. Bone formation in the implants, assessed by X-ray, progressed steadily in the follow-up period. Two patients achieved full functional recovery at 6 months after surgery, one patient at 12 months after surgery. The present report shows that large segmental bone reconstruction can be achieved in humans using osteoprogenitor cells. This technique can be improved by a more biodegradable and more biomechanically resistant scaffold use.

Autologous chondrocyte implant (ACI) is a very effective technique in the treatment of chondral lesions in order to restore normal hyaline cartilage. This technique, reported for the first time by Peterson in 1994, is advised for young or middle-aged. active patients with a single painful chondral injury (3/4 grade of Outerbridge scale), starting from more than 2 cm². New tissue engineering techniques with the use of biomaterial derived from hyaluronic acid (HYAFF matrix) provide ideal support for the culture and proliferation of chondrocytes, allowing at the same time arthroscopic implant. There are many advantages of arthroscopic techniques: easy implant and less pain post-operatively; however, the indications for arthroscopic technique are still restricted: single chondral inury, 2–6 cm² in size and localisation at the femoral condyles.

At the Department of Orthopaedic Surgery of the University “ Federico II ” of Naples starting from January 1996 to the present, 29 patients were treated with ACI. Eight patients (six men and two women) had an arthroscopic implant. Median age was 18; in seven patients an OCD of the medial femoral condyle was present and just one patient had a post-traumatic injury of the medial femoral condyle. Hyalograft was used in all cases. All patients underwent CPM starting from the second post-operative day and full charge was allowed after 2 months. All patients were evaluated by clinical examination with IKDC score and functional score (Tegner) at 3, 6 and 12 months after surgery and with a MNR at 6 and 12 months after surgery and then every year.

Good results were found subjectively in 88% of the patients, with a complete lack of pain in 70% cases. Using the IKDC score good results were found in 85% of the cases (average score 90). With the Tegner score we reported an improvement in the level of activity in 60% of the cases.

The MNR images, performed with standard sequences, fat-suppressed and in the last cases with dGEMRIC, showed the presence of regeneration tissue inside the chondral defects, with a signal very similar to that of the cartilage tissue, sometimes slightly deeper.

Our experience shows that ACI is an effective way of treating chondral lesions with excellent results. We think that progress in the field of biomaterials will extend the indications for arthroscopic techniques, also allowing implants in larger lesions and at other sites.

Rotational defects of the lower limb are frequently encountered and often underestimated. In fact, many symptoms in the lower joint can be related to rotational alteration in the lower leg. These problems are often more visible in the knee joint because they reflect the rotational problems of proximal and distal femur and tibia, respectively. The extensor apparatus, due to the fact that it interacts with both bones, is the more affected joint. Many authors have demonstrated that femoral anteversion increases stress on the patello-femoral joint due to excessive lateralisation of the patella. In the same manner, distal femur internal rotation increases the stress due to altered tracking of the patella during ROM.

Valgus knee places stress on the patello-femoral joint, increasing the Q angle and determining a retraction of the lateral structure that causes stress on the lateral patellar face and altered patellar scratch during ROM. External tibial rotation also has been documented to increase the Q angle and patellar tilt, causing excessive stress on the patello-femoral joint. Valgus pronation of the foot, increasing the valgus stress on the knee, can contribute to patello-femoral symptoms, increasing the muscle imbalance at this level.

These documented alterations contribute together with other anatomical abnormalities, such as trochlear dysplasia or muscle hypoplasia, in creating the high variability of patello-femoral symptoms that are observed. Rotational deformity of the lower leg therefore represents a frequently encountered pathological condition that must be taken into account when treating patello-femoral symptoms.

A tissue engineering-based approach has become a possible solution for the treatment of chondral lesions. Actually, autologous chondrocytes seeded on biodegradable scaffolds for cell proliferation were successfully developed. However, these techniques promote cartilaginous but not bony regeneration. Therefore a new experimental approach involving mesenchymal stem cells (MSC) has been introduced.

A 31-year-old man affected by massive osteonecrosis of the right femoral head was selected to begin this study. The MSC were isolated from the bone marrow harvested from the patient’s iliac crest. After a 3-week monolayer expansion, cells were seeded and cultured onto hyaluronan-based three-dimensional scaffolds and DBM spongy chips, used to regenerate the cartilaginous and the bony portion, respectively. After a 2-week cultivation, constructs were implanted inside the osteochondral defect using the transtrochanteric approach under arthroscopic control. The patient underwent clinical, X-ray and MRI control during the first 6 months after operation.

Pluripotent MSC may be a promising strategy for osteochondral defect reconstruction due to their capacity to differentiate in vivo along chondrocytic and osteoblastic lineages. This ability, combined with two different kinds of three-dimensional scaffolds, permits simultaneous bone and cartilage tissue regeneration. The preliminary results are encouraging but a more precise judgement of the effectiveness of this method requires longer follow-up.

Neglected rupture of quadriceps tendon is an infrequently occurring lesion resulting from sport, but it is very interesting as regards the physiological and functional repercussions. The lesion is common in football players. The pathogenesis is a flexion trauma of knee. Many authors point out the importance of a pre-existent degeneration due to exogenous and endogenous factors. Pain, inextensible knee, ecchymosis, axe hit are a common presentation in acute events, difficult knee extension and pain in chronic. X-ray study shows calcification at the tendon-bone junction.

The treatment of neglected rupture of quadriceps tendon is surgical. If a defect of 5 cm or more is present between the ends of tendon the fascia lata can be used to correct the gap. When the ends can be apposed an end-to-end repair is possible. We treated a neglected rupture of quadriceps femoris muscle tendon in a bodybuilder with a particular technique: we stripped and harvested the semitendinosus and gracilis tendon and sutured them together. Then we made a transverse hole in the mid-portion of the patella; the tendons were passed through the transverse hole in the patella and sutured with the lateral, medial and intermendial vastus, and with the rectum femoral. At 6-month follow-up the patient has no pain and stability is improved, a practical range of knee motion regained. Full forceful extension is not completely restored.

Valgus deformity of the knee in relation to femoral dysplasia and post-traumatic varus deformity in relation to supracondylar fracture often needs to be corrected with varus or valgus distal femoral osteotomy. This procedure must be very precise to avoid compartimental overstress. However, in valgus knee the deformity is very often not only bi-planar but also tri-planar. In fact, the rotational defect of the distal femur can play an important role in determining the clinical symptoms and in altering the pathway of patello-femoral joint.

Therefore, correcting only the valgus deformity does not solve the clinical symptoms related to incorrect rotation of distal femur. The same problem is often encountered in distal femoral deformity in relation to supracondylar fracture. The bad alignment of the healed fracture is very often on the three planes and this fact has always to be taken into account during the pre-operative planning.

The pre-operative planning is fundamental and CT of the knee joint with reference to hip and ankle must be performed to evaluate the degree of rotational deformity that must be corrected. During surgery after the correction of valgus or varus deformity is fundamental to re-check the femur rotation, because the osteotomy automatically changes also the rotation of the distal femur. However, this correction may be insufficient to correct the rotation that can maintain clinical symptoms in the patello-femoral joint. If this is the case, an additional correction in external rotation is usually necessary to achieve an overall correction of distal femoral deformity.

In our opinion, the difficulties and accuracy necessary to correct this type of pathology are often underestimated.

Autologous chondrocyte transplantation has become a possible solution for the treatment of chondral knee lesions. In the last years matrix autologous chondrocyte transplantation procedures were developed by various scientists. We selected a biodegradable, hyaluronian-based biocompatible scaffold for cell proliferation. This nonwoven three-dimensional structure consists of a network of 20 – B5-thick fibers with interstices of variable sizes which constitute an optimal physical support to allow cell-cell contacts, cluster formation, and extracellular matrix deposition in order to create a bioengenerized cartilage Hyalograft C. The easy handling of Hyalograft C in open surgery has suggested us to investigate its possible use by an arthroscopic procedure.

Arthroscopic technique has been used from December 2000 in 88 cases. At December 2003 45 patients achieved at least 1 year follow up and 22 patients – 2 years follow up.

All the patients were clinically evaluated was analyzed according to the International Repair Cartilage Society score at 12 and 24 months. Returning back to sport was also recorded. We were able to obtain CT scans or MRI images for all patients at 6, 12 and 24 months of follow up.

No complications related to the implant and no serious adverse events were observed during the treatment and follow up period. The IKDC objective score improved after 12 months in all patients, showing a normal or nearly normal knee in 96,7% of patients. The mean IKDC subjective score obtained was 41,3 at baseline, 76.9 at the 12 months follow-up control, and 75,9 after 24 months. The worsening of IKDC score was noted in 1 of 22 patients analyzed at 12 and 24 months follow up.

A second look arthroscopy was performed in 11 patients at 12 months follow up and a complete healing of the defect and the excellent quality of regenerated cartilage was noted at macroscopic examination. The histological evaluation in 6 cases has demonstrated the hyaline type of new cartilage, although not completely mature.

This matrix autologous chondrocyte transplantation procedure avoids the use of periosteal flap, simplify the surgical procedure and permit to perform the arthroscopic implant. Thus, complications as hypertrophy or ossification of periosteal flap are avoided and the surgical morbidity and the recovery time for the patient are extremely reduced. The preliminary clinical and histological results are encouraging but the decree absolute on the efficiency of this method will be assessed at longer follow up.