Matteo Denti

Definition and classification of early osteoarthritis of the knee

With the emerging interest in regenerative medicine and tissue engineering, new treatment modalities being developed for joint disorders including joint surface lesions and articular cartilage defects. The clinical outcome of these novel approaches appears rather unpredictable and is due to many reasons but definitely also linked to the patient profile. As a typical example, symptomatic articular cartilage lesions can be presented in an otherwise normal joint, or associated with several other joint tissue alterations including meniscal lesions and abnormalities of the underlying bone. The outcome of novel treatments may well be influenced by the status of the whole joint, and the potential to develop osteoarthritis. To better identify the patients at risk and responders to certain treatments, it is of use to define and most importantly classify patients with “early osteoarthritis”. Here, classification criteria for this group of patients are presented, allowing a more defined and accurate inclusion in clinical trials in the future.

Anterior cruciate ligament mechanoreceptors. Histologic studies on lesions and reconstruction.

The fate of mechanoreceptors was studied in torn and reconstructed anterior cruciate ligaments in animals and in humans. In untreated anterior cruciate ligament lesions in humans, morphologically normal mechanoreceptors remained in the ligament for 3 months after the injury. After that time, their number gradually decreased. By the 9th postinjury month, only a few free nerve endings were present. Even free nerve endings were totally absent in the biopsy specimens from 1-year-old lesions. In experimental animals, anterior cruciate ligament reconstruction with autologous patellar tendon resulted in the presence of mechanoreceptors in the reconstructed anterior cruciate ligament. When an artificial ligament was used, no mechanoreceptors were found. Morphologically normal mechanoreceptors were present in 2 patients with a lax biologic anterior cruciate ligament reconstruction 9 and 10 years after the operation.

Revision Anterior Cruciate Ligament Reconstruction: Causes of Failure, Surgical Technique, and Clinical Results

BACKGROUND Revision of an anterior cruciate ligament reconstruction is a complicated and delicate clinical procedure whose results, theoretically, are less satisfactory than those of the first operation. HYPOTHESIS The outcome of a revised anterior cruciate ligament surgery is comparable to primary anterior cruciate ligament reconstruction, with a rate of success around 70% to 80%. STUDY DESIGN Case series; Level of evidence, 4. METHODS A total of 66 revisions of anterior cruciate ligament reconstructions were carried out from September 2000 to September 2004. Patients with concomitant instability and those with alterations in the weightbearing axis of the lower limbs were not included. Sixty patients were followed from 24 to 72 months: 50 clinically and 10 by a phone interview. Six patients were lost to follow-up due to changes of address. RESULTS Lysholm scores were 57% excellent (95-100 points), 13% good (84-94 points), 22% fair (63-83 points), and 8% poor (<64 points). A total of 68% of patients had negative Lachman tests, 20% had positive tests with a hard end point, 10% had positive results, and 2% had very positive results. Stabilometric evaluation with the KT-1000 arthrometer at the maximum load showed that 56% of patients had <3 mm side-to-side difference, 34% had between 3 and 5 mm, and 10% had 6 to 10 mm. The International Knee Documentation Committee scores were 36% excellent (class A), 46% good (class B), and 18% fair (class C). The percentage of patients who resumed sport at the same level was 78%, compared with 58% after their primary reconstruction. CONCLUSION The results of these anterior cruciate ligament reconstruction revision surgeries are close to those achieved by other series of primary reconstructions with a little less satisfactory results. We attribute the high success rate to the strict application of the same technique and the confinement of revision to motivated patients. It should be noted, however, that follow-up is only at the midterm stage (mean, 41.9 months).

Infectious and thromboembolic complications of arthroscopic shoulder surgery

HYPOTHESIS This study investigates the rate of infectious and thromboembolic complications in shoulder arthroscopy and their association with pharmacologic prophylaxis. MATERIALS AND METHODS On behalf of the Italian Society for Knee Surgery, Arthroscopy, Sport Traumatology, Cartilage and Orthopaedic Technologies (SIGASCOT), we asked the members to complete an on-line Web survey about their experiences and strategies of prophylaxis in shoulder arthroscopy. RESULTS In the period 2005-2006, 9385 surgeries were performed. We report 15 infections and 6 DVTs. The overall rate of infections was 0.0016 (1.6/1000) and the rate of DVTs was 0.0006 (0.6/1000) CONCLUSION The association between infection and antibiotic prophylaxis was significant (P=0.01); however, the risk of DVTs was not decreased with heparin prophylaxis. LEVEL OF EVIDENCE Level 3.

Pre- and postoperative intra-articular analgesia for arthroscopic surgery of the knee and arthroscopy-assisted anterior cruciate ligament reconstruction A double-blind randomized, prospective study

Abstract We tested the effectiveness of different intra-articular analgesics and of pre-emptive intra-articular analgesia for arthroscopy-assisted anterior cruciate ligament reconstruction (ACLR) and for operative knee arthroscopy. Eighty-two patients underwent operative knee arthroscopy under selective subarachnoid anaesthesia (group A), and 60 patients underwent arthroscopy-assisted ACLR under general anaesthesia (group B). Patients were randomly assigned to intra-articular analgesic treatment as follows. Group A: 1, morphine 2 mg; 2, preoperative morphine 2 mg; 3, morphine 5 mg; 4, preoperative morphine 5 mg; 5, bupivacaine 0.25% 20 ml; 6, bupivacaine 0.25% 20 ml + morphine 2 mg; 7, saline solution 20 ml. Group B: 1, morphine 2 mg; 2, morphine 5 mg; 3, preoperative morphine 5 mg; 4, bupivacaine 0.25% 20 ml; 5, bupivacaine 0.25% 20 ml + morphine 2 mg; 6, saline solution 20 ml. All opioids were diluted in 20 ml of saline solution. After postoperative administration the tourniquet was left in place for 10 min. After preoperative administration the intra-articular surgical procedure was delayed for about 5–10 min. In the postoperative period we recorded: total consumption of ketoprofen given i.v. on demand as rescue analgesic treatment; pain scores before surgery and at 1st, 3rd, 6th, 12th and 24th h; occurrence of local anaesthetic or opioid side-effects. Group A (operative knee arthroscopy): all morphine groups (A1, A2, A3, A4) and the bupivacaine group (A5) did not require ketoprofen postoperatively (P < 0.01 vs both groups A6 and A7). Pain scores did not differ significantly among groups. The percentage of patients reporting higher pain scores than before surgery was larger in control group A7 and in bupivacaine groups A5, A6 (83%, 40%, 60%, respectively) and lower in morphine groups A1, A2, A3, A4 (25%, 16%, 27%, 23%, respectively). Group B (ACLR): total consumption of ketoprofen was lowest in groups B2 and B3 (P < 0.001 vs all other treatments and vs control group). The percentage of patients who did not require any rescue analgesic was 60% in group B3, 50% in group B2, 32% in group B5 and 0% in all other groups. No-side effects occurred in any patient. Intra-articular analgesia is safe and effective for arthroscopic knee surgery. Morphine provides a better pain control both in operative knee arthroscopy patients and in ACLR. A 2 mg dose is adequate for operative knee arthroscopy but not for ACLR, where higher dosages are required (5 mg). Pre-emptive intra-articular morphine provides better analgesia than postoperative administration.

Why menisci show higher healing rate when repaired during ACL reconstruction? Growth factors release can be the explanation

PurposeHealing rate of meniscus repair is higher when the suture is associated with anterior cruciate ligament reconstruction. A possible explanation can be a different pattern of release of growth factors between anterior cruciate ligament reconstruction and isolated meniscus surgery. Hypothesis of this study is that the concentrations of bFGF, TGF-β and platelet-derived growth factor (PDGF) in joint fluid, immediately after single-bundle anterior cruciate ligament reconstruction and arthroscopic partial meniscectomy, can be different.MethodsTwenty consecutive patients underwent partial medial meniscectomy and twenty consecutive patients underwent single-bundle anterior cruciate ligament reconstruction with hamstring grafts were enrolled in the study. Thirty minutes after the end of the surgical procedure, a sample of joint fluid, as well of venous blood, was collected from all the patients. Concentrations of growth factors were determined by enzyme-linked immunosorbent assay.ResultsThe peripheral blood concentration of TGF-β, bFGF and PDGF was comparable between partial meniscectomy and anterior cruciate ligament reconstruction groups. No differences between the two surgical techniques were also found in term of TGF-β and bFGF joint fluid concentration, whereas joint PDGF concentration of anterior cruciate ligament reconstruction patients was significantly higher than the one found in partial meniscectomy patients.ConclusionsA significant growth factors release was detected in the knee joint during arthroscopic surgery. PDGF concentration was significantly higher in anterior cruciate ligament reconstructed knee than in the meniscectomy group. PDGF can play an important role enhancing the healing response of meniscus suture and can be one of the biological reasons of the higher meniscal healing rate in anterior cruciate ligament reconstructed knee.

Prevalence of Associated Lesions in Anterior Cruciate Ligament Reconstruction Correlation With Surgical Timing and With Patient Age, Sex, and Body Mass Index

Background: Knee instability resulting from anterior cruciate ligament (ACL) rupture is an important risk factor for the onset of meniscal tears and cartilage injuries. A delay of the ligament reconstruction further increases this risk. There is currently no agreement on the right time for surgical ACL reconstruction. Purpose: To verify the correlation of time to ACL reconstruction, patient age, sex, and body mass index (BMI) with the prevalence of meniscal tears and cartilage injuries, as well as to identify the proper surgical timing to decrease the risk of developing associated injuries. Study Design: Cohort study; Level of evidence, 3. Methods: The medical records of 988 patients who underwent primary ACL reconstruction between January 2010 and May 2014 were analyzed to collect data on the prevalence of meniscal tears and cartilage injuries, surgical timing, and patient sex, age, and BMI. Logistic regression was performed to estimate the association between the prevalence of intra-articular lesions and the independent variables of surgical timing, sex, age, and BMI. Results: The risk of developing at least an associated lesion increased by an average of 0.6% for each month of delay of surgical reconstruction. The odds ratio (OR) for developing an intra-articular lesion was 1.989 (95% CI, 1.403-2.820) in those waiting more than 12 months for ACL reconstruction. A 12-month delay for the intervention nearly doubled the risk of developing a medial meniscal tear (OR, 1.806 [95% CI, 1.317-2.475]) but did not modify the risk for the lateral meniscus (OR, 1.183 [95% CI, 0.847-1.653]). Concerning cartilage lesions, the risk after a 12-month delay increased in the medial compartment (femoral condyle: OR, 2.347 [95% CI, 1.499-3.676]; tibial plateau: OR, 5.574 [95% CI, 1.911-16.258]). In the lateral femoral condyle, the risk became significant in patients who underwent surgery more than 60 months after ACL injury as compared with those treated in the first 3 months (OR, 5.949 [95% CI, 1.825-19.385]). Lateral tibial plateau lesions did not seem to increase significantly. Male sex was a risk factor for the onset of lateral meniscal tears (OR, 2.288 [95% CI, 1.596-3.280]) and medial tears (OR, 1.752 [95% CI, 1.280-2.399]). Older age (OR, 1.017 [95% CI, 1.006-1.029]) and increased BMI (OR, 1.120 [95% CI, 1.072-1.169]) were risk factors for the occurrence of at least 1 associated lesion. Conclusion: ACL reconstruction within 12 months of injury can significantly reduce the risk of meniscal tears and chondral lesions. The close association between BMI and prevalence of associated lesions suggests that attention be paid to patients with an elevated BMI when considering the timing of ACL reconstruction surgery.

Long-term results of the Leeds-Keio anterior cruciate ligament reconstruction.

This paper discusses the long-term results of the anterior cruciate ligament (ACL) reconstruction with the Leeds-Keio (LK) prosthetic ligament. For this type of reconstruction we used arthrotomy and an arthroscopy-assisted technique. The fixation was obtained with two bone plugs, and the distal portion was also attached with a staple. A postoperative protocol was used with a progressive range of motion and weight bearing after 50 days. We performed 50 LK operations in professional and amateur athletes aged 17–39 years with an isolated anterior instability. We reviewed at follow-up (5–7 years) 37 patients; 8 were lost, and 5 had a subsequent failure. At the Lysholm score the patients were classified: 19 excellent, 13 good, 3 fair, and 2 poor. At the IKDC grading the patients were classified as follows: 2 class A, 22 B, 8 C, and 5 D. The Lachman test was 1+ in 15 patients, 2+ in 7, 3+ in 2, and negative in 13: pivot shift was 1+ in 9, 2+ in 7, 3+ in 2, and negative in 25. Results of the KT 1000 test at 30 Ib side to side was <3 mm in 23 patients, 3–5 mm in 6, 6–10 mm in 6, and >10 mm in 2. In view of the results observed and the progressive deterioration over the years, this procedure should no longer be performed as an ACL substitute.

BONE ASSESSMENT AFTER TOTAL KNEE ARTHROPLASTY BY DUAL-ENERGY X-RAY ABSORPTIOMETRY : ANALYSIS PROTOCOL AND REPRODUCIBILITY

Abstract. Bone quality is important for the success of joint prostheses implantation, and the assessment of bone density after total knee arthroplasty by means of dual-energy X-ray absorptiometry may be useful for monitoring implant stability. The aim of this study is to suggest a validated analysis protocol for the assessment of bone status after total knee arthroplasty. A dedicated densitometric analysis protocol of five regions of interest was designed, and 10 subjects who had received an uncemented knee prosthesis (8 females and 2 males, aged 55–74 years) underwent three consecutive scans in posteroanterior and lateral projections, with repositioning after each scan to test the suitability and reproducibility of the protocol. The reproducibility of the measurement of bone mineral content and density in the femoral and tibial regions ranged, respectively, from 2.1% to 4.1%, from 0.9% to 2.6% for the posteroanterior scans, and from 2.7% to 5.6% and from 2.3% to 4.7% for the lateral scans, depending on the considered region. Our results confirm that the suggested protocol allows precise assessment of bone mineral content and density, and that dual-energy X-ray absorptiometry is reliable for the evaluation of bone mass around prosthetic implants.

Prophylactic use of antibiotic-loaded bone cement in primary total knee replacement

Despite significant advances in intraoperative antimicrobial procedures, deep infection remains the most devastating complication following total joint arthroplasty. Clinical studies’ results and safety profile of antibiotic-loaded bone cement are discussed in this review. Antibiotic bone cement prophylaxis is a safe and effective strategy in reducing the risk of deep infection following primary total joint arthroplasty.