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Andrea Ferretti

Publications and source records attributed to Andrea Ferretti.

12 recordsLinked to original sources
PubMed2006

The effect of accelerated, brace free, rehabilitation on bone tunnel enlargement after ACL reconstruction using hamstring tendons: a CT study.

The mechanism of bone tunnel enlargement following anterior cruciate ligament (ACL) reconstruction is not yet clearly understood. Many authors hypothesized that aggressive rehabilitation protocols may be a potential factor for bone tunnel enlargement, especially in reconstructions performed with hamstrings autograft. The purpose of this study was to evaluate the effect of a brace free rehabilitation on the tunnel enlargement after ACL reconstruction using doubled semitendinosus and gracilis tendons (DGST): our hypothesis was that early post-operative knee motion increase the diameters of the tibial and femoral bone tunnels. Forty-five consecutive patients undergoing ACL reconstruction for chronic ACL deficiency were selected. All patients were operated by the same surgeon using autologous DGST and the same fixation devices. Patients with associated ligaments injuries and or severe chondral damage were excluded. The patients were randomly assigned to enter the control group (group A, standard post-operative rehabilitation) and the study group (group B, brace free accelerated rehabilitation). A CT scan was used to exactly determine the diameters of both femoral and tibial tunnels at various levels of lateral femoral condyle and proximal tibia, using a previously described method [17]. Measurements were done by an independent radiologist in a blinded fashion the day after the operation and at a mean follow-up of 10 months (range 9-11). Statistical analysis was performed using paired t-test. The mean femoral tunnel diameter increased significantly from 9.04 +/- 0.05 (post-operative) to 9.30 +/- 0.8 mm (follow-up) in group A and from 9.04 +/- 0.03 to 9.94 +/- 1.12 mm in group B. The mean tibial tunnel diameter increased significantly from 9.03 +/- 0.04 to 10.01 +/- 0.80 mm in group A and from 9.04 +/- 0.03 to 10.60 +/- 0.78 mm in group B. The increase in femoral and tunnel diameters observed in the study group was significantly higher than that observed in the control group. Our results suggest that bone tunnel enlargement after ACL reconstruction using hamstrings autograft can be increased by an accelerated, brace free, rehabilitation protocol.

Adolescent↗
PubMed2006

Bone tunnel enlargement after ACL reconstruction using autologous hamstring tendons: a CT study.

PURPOSE: To evaluate prospectively the increase in the size of the tibial and femoral bone tunnel following arthroscopic anterior cruciate ligament (ACL) reconstruction with quadrupled-hamstring autograft. METHODS: Twenty-five consecutive patients underwent arthroscopic ACL reconstruction with quadrupled-hamstring autograft. Preoperative clinical evaluation was performed using the Lysholm knee score, Tegner activity level, and International Knee Documentation Committee forms and a KT-1000 arthrometer (side to side). Computed tomography (CT) of the femoral and tibial tunnel was performed on the day after operation in all cases and at mean follow-up of 10 months (range 9-11 months). RESULTS: All of the clinical evaluation scales performed showed an overall improvement. The postoperative anterior laxity difference was <3 mm in 16 patients (70%) and 3-5 mm in seven patients (30%). The mean average femoral tunnel diameter increased significantly (3%) from 9.04+/-0.05 mm postoperatively to 9.3+/-0.8 mm at 10 months; tibial tunnel increased significantly (11%) from 9.03+/-0.04 mm to 10+/-0.8 mm. There were no statistically significant differences between tunnel enlargement, clinical results, and arthrometer evaluation. CONCLUSIONS: The rate of tunnel widening observed in this study seems to be lower than that reported in previous studies that used different techniques. We conclude that an anatomical surgical technique and a less aggressive rehabilitation process influenced the amount of tunnel enlargement after ACL reconstruction with doubled hamstrings.

Adolescent↗
PubMed2006

Revision anterior cruciate ligament reconstruction with doubled semitendinosus and gracilis tendons and lateral extra-articular reconstruction.

BACKGROUND: The outcome of revision anterior cruciate ligament reconstruction has only rarely been reported. The purpose of this study was to evaluate the results of revision anterior cruciate ligament surgery with use of an autogenous doubled semitendinosus and gracilis graft in association with an extra-articular procedure. METHODS: Between 1997 and 2003, thirty patients underwent a repeat reconstruction of a previously reconstructed torn anterior cruciate ligament with use of a doubled semitendinosus and gracilis graft combined with an extra-articular reconstruction. Primary reconstruction had been done with an autogenous patellar tendon graft in twenty-six patients and with a prosthetic ligament in four patients; the average time from the primary reconstruction to the revision was five years. Functional outcomes, graft survival, and radiographic outcomes were evaluated at a mean of five years. A graft was considered to have failed when a revision was done or when the side-to-side difference on KT-1000 arthrometer testing was >5 mm and/or the pivot-shift test grade was greater than a trace. RESULTS: One patient underwent another revision reconstruction because of graft failure at three years postoperatively. The mean International Knee Documentation Committee (IKDC) subjective knee score for the remaining twenty-nine patients was 84 +/- 12 points, and the mean Lysholm knee score was 90 +/- 10 points. The side-to-side difference as measured with the KT-1000 arthrometer with maximum manual force was <3 mm in twenty patients (of the twenty-eight who returned for follow-up), between 3 and 5 mm in six patients, and >5 mm in two patients. The result of the pivot shift examination was normal in fifteen patients, slightly positive in eleven patients, and positive in two patients. Twenty-five percent of the patients showed no radiographic signs of degenerative joint disease. CONCLUSIONS: Revision anterior cruciate ligament reconstruction with use of an autogenous doubled semitendinosus and gracilis graft combined with an extra-articular procedure provided satisfactory functional outcomes, with a failure rate of 10%.

Adult↗
PubMed2005

Effect of cyclic loading on new polyblend suture coupled with different anchors.

BACKGROUND: Secure tendon-to-bone fixation is essential for successful rotator cuff repair. Biomechanical properties of devices used in rotator cuff repair should be better understood. PURPOSE: To evaluate the response to incremental cyclic loading of 6 different anchor-suture complexes commonly used in rotator cuff repair. STUDY DESIGN: Controlled laboratory study. METHODS: Two absorbable anchors 5 mm and 6.5 mm in diameter and 1 metallic anchor, coupled with Ethibond or FiberWire, were tested on 5 pairs of fresh-frozen human cadaveric shoulders. An incremental cyclic load was applied until failure using a Zwich-Roell Z010 electromechanical testing machine. The ultimate failure load and mode of failure were recorded. An analysis of variance model was used for statistical analysis. RESULTS: The FiberWire suture coupled with both absorbable and metallic anchors provided statistically significantly stronger fixation. However, although the metallic anchors in most cases failed because of slippage of the anchor, absorbable anchors failed because of rupture of the eyelet. CONCLUSIONS: The FiberWire seems to increase the strength of fixation devices under cyclic load using both absorbable and metallic anchors, with relevant differences in failure mode (slippage of the metallic anchor and eyelet failure in the absorbable anchor). CLINICAL RELEVANCE: Use of the FiberWire suture might change the mode of failure of the suture-anchor complexes.

Aged↗
PubMed2005

Evolgate fixation of doubled flexor graft in anterior cruciate ligament reconstruction: biomechanical evaluation with cyclic loading.

BACKGROUND: The weakest points in hamstrings anterior cruciate ligament reconstruction are its points of fixation, especially on the tibial side. Methods for graft fixation to bone should be strong enough to avoid failure, stiff enough to restore load-displacement response, and secure enough to resist slippage under cyclic loading. HYPOTHESIS: Biomechanical properties of the interference screw can be improved by reinforcing the walls of the tunnel with a metal spiral (Evolgate fixation). STUDY DESIGN: Controlled laboratory study. METHODS: Three paired tests were performed using common digital extensor bovine tendons fixed to porcine tibias with interference screw, Intrafix, and Evolgate; critical graft fixation conditions were simulated by applying subsequent cycles to the graft before loading the graft until failure. RESULTS: The strength, stiffness, and resistance to slippage of the Evolgate were significantly higher than those of the interference screw; the ultimate failure load of the Evolgate was significantly higher than that of the Intrafix (1058+/-130 N and 832+/-156 N, respectively; P=.02). No statistically significant differences were found between Evolgate and Intrafix regarding the stiffness and slippage under cyclic load. CONCLUSION: Evolgate fixation seems to be stronger, stiffer, and more resistant to slippage than is interference screw fixation of similar length, and it is stronger but not stiffer than Intrafix. CLINICAL RELEVANCE: The Evolgate provides structural properties that seem to be appropriate for an intensive rehabilitation after anterior cruciate ligament reconstruction using a doubled semitendinosus and gracilis graft.

Alloys↗
PubMed2003

Operative treatment of chronic Achilles tendinopathy.

Seventy-six patients with Achilles tendinopathies (n=86) operated between 1980 and 1995 were retrospectively evaluated at an average follow-up of 13 (5-21) years. Total or gross partial ruptures were excluded. Patients' average age at surgery was 38 (18-58) years. The majority of patients were active in competitive or recreational sports. Tendinopathies were classified in peritendinitis, tendinosis, insertional tendinopathies, and mixed forms. The surgical technique depended entirely on the pathology encountered. For 32 cases of peritendinitis, results were excellent in 26, good in four, and poor in two. For eight cases of tendinosis, results were excellent in four and good in four. For 34 cases of insertional tendinopathy, results were excellent in 22, good in four, fair in four, and poor in four. For 12 cases of mixed tendinopathies, results were excellent in ten and good in two. Forty-nine patients (52 cases) were able to return to sport at the desired level.

Achilles Tendon↗
PubMed2003

Electronic properties of polymer crystals: the effect of interchain interactions.

We present a theoretical study of the transport parameters in a prototype conjugated-polymer, poly-para-phenylenevinylene, in two different possible crystalline packings. Our analysis is performed through density-functional electronic structure calculations, and allows one to obtain the fundamental parameters describing charge transport. The transfer integrals are found to be a crucial quantity to appreciate the effects of crystalline aggregation on conduction properties: our results indicate that interchain interactions can be viewed as a tunable parameter for the design of efficient electronic devices based on organic materials.

Journal Article↗
PubMed2003

The Evolgate: a method to improve the pullout strength of interference screws in tibial fixation of anterior cruciate ligament reconstruction with doubled gracilis and semitendinosus tendons.

PURPOSE: The goal of the study was to investigate the biomechanical properties of a new device for tibial fixation in arthroscopic anterior cruciate ligament reconstruction using doubled semitendinosus and gracilis tendons. TYPE OF STUDY: Biomechanical study. METHODS: This study compares the initial pullout strength, stiffness, and failure modes of 7 pairs of 4-strand human semitendinosus and gracilis grafts fixed to porcine tibias using either the Evolgate (Citieffe, Bologna, Italy) or 1 round threaded titanium interference screw. Structural tests of the graft fixation method tibia complexes were performed using a materials testing machine (MTS Bionix 855, Minneapolis, MN) at a strain rate of 50 mm/second. RESULTS: The mean failure load was 1,237 +/- 191 N for the Evolgate and 537 +/- 65 N for the interference screw (P <.05) and the mean stiffness was 168 +/- 37 N/m for the Evolgate and 105 +/- 17 N/m for the interference screws (P < or =.05). Although in all the cases fixed with the Evolgate failure occurred because of tendon rupture inside the tibial tunnel close to the fixation device, in 4 of the 7 cases fixed with interference screws, failure occurred because of tendon slippage at the fixation site. CONCLUSIONS: These results indicate that initial pullout strength of hamstring tendon graft interference screw fixation can be significantly increased using the Evolgate. In fact, because the screws purchase only in the cancellous bone, the Evolgate reinforces the walls of the tibial tunnel with a titanium involute, avoiding the loss of fixation strength related to the low density of the cancellous bone of the proximal metaphysis of the tibia.

Adult↗
PubMed2002

Conservative treatment of subtalar dislocations.

Forty-five patients who presented between 1983 and 1998 with acute closed dislocation of the subtalar joint were selected for this study. There were 37 medial and eight lateral dislocations. The mean follow-up was 7.5 years (range: 2-17 years). The mean American Orthopaedic Foot and Ankle Society Hindfoot Score (AOFAS) at follow-up was 84. Subtalar fusion was required in one patient with persistent severe hind-foot instability. There was no significant difference in the AOFAS score between medial and lateral subtalar dislocations. We conclude that pure subtalar dislocation produced by low energy trauma, promptly reduced and immobilised for 4 weeks has a favourable long-term outcome.

Adolescent↗
PubMed2002

Patellar tendinosis: a follow-up study of surgical treatment.

BACKGROUND: Patellar tendinopathy (jumper's knee) is an overuse syndrome that frequently affects athletes. A retrospective study was done to analyze the results at a minimum of five years after the performance of a surgical technique in competitive athletes. METHODS: From 1985 to 1995, thirty-two patients (thirty-eight knees) affected by patellar tendinopathy were treated surgically after failure of nonoperative treatment. All knees were operated on by the same surgeon using the same surgical technique: longitudinal splitting of the tendon, excision of any abnormal tissue that was identified, and resection and drilling of the inferior pole of the patella. The results in twenty-seven patients (thirty-three knees), including twenty-two athletes (twenty-seven knees) who were still involved in sports activities (or wished to still be involved) at a competitive level at the time of final follow-up, were reviewed at a mean of eight years postoperatively. The results were evaluated according to symptoms and the ability to return to full sports activities. RESULTS: The result was excellent in twenty-three knees (70%), good in five, fair in one, and poor in four at the time of the long-term follow-up. Eighty-two percent of the patients who tried to pursue sports at their preinjury level were able to do so, and 63% of those knees were totally symptom-free. CONCLUSIONS: The outcome of the described surgical treatment appears to be satisfactory; however, the results are less predictable in volleyball players.

Adolescent↗
PubMedDate not supplied

Regeneration of the semitendinosus tendon after its use in anterior cruciate ligament reconstruction: a histologic study of three cases.

We describe the histologic course of regenerated tissue simulating the semitendinosus tendon in three patients after anterior cruciate ligament reconstruction with doubled semitendinosus and gracilis tendons. Specimens were retrieved during revision surgery for removal of tibial hardware at 6, 24, and 27 months, respectively. Resisted flexion during physical examination in all patients revealed a "string" on the posteromedial aspect of the knee that was quite evident, suggesting the presence of a regenerated semitendinosus tendon. At surgery, a well-defined fibrous band was identified about 3 cm proximal and medial to the pes anserinus, reproducing the pathway of the native semitendinosus tendon. In the specimen retrieved 6 months postoperatively, a prominent fibroblastic proliferation was observed together with a few vessels surrounded by fibrous tissue; only a few bundles of well-oriented collagen fibers were present, together with scattered rows of spindle-shaped cells. In both of the specimens retrieved 2 years postoperatively, all of the central, thicker portion of each specimen was occupied by well-oriented tendon-like fibers together with uniformly distributed spindle-shaped cells that had the appearance of mature tenocytes arranged in orderly rows. These findings help us to understand the progression of the healing process at the harvest site and the nature of the regenerated semitendinosus tendon, which has previously been investigated only by studies of clinical and functional outcomes and by imaging studies.

Adult↗