Wednesday, November 9, 2011

Tissue Engineering and Regenerative Medicine Strategies in Meniscus Lesions.


Arthroscopy. 2011 Oct 
Pereira H, Frias AM, Oliveira JM, Espregueira-Mendes J, Reis RL.

Abstract
PURPOSE:
The aim of this systematic review was to address tissue engineering and regenerative medicine (TERM) strategies applied to the meniscus, specifically (1) clinical applications, indications, results, and pitfalls and (2) the main trends in research assessed by evaluation of preclinical (in vivo) studies.

METHODS:
Three independent reviewers performed a search on PubMed, from 2006 to March 31, 2011, using the term "meniscus" with all of the following terms: "scaffolds," "constructs," "cells," "growth factors," "implant," "tissue engineering," and "regenerative medicine." Inclusion criteria were English language-written, original clinical research (Level of Evidence I to IV) and preclinical studies of TERM application in knee meniscal lesions. Reference lists and related articles on journal Web sites of selected articles were checked until prepublication for potential studies that could not be identified eventually by our original search. The modified Coleman Methodology score was used for study quality analysis of clinical trials.

RESULTS:
The PubMed search identified 286 articles (a similar search from 2000 to 2005 identified 161 articles). Non-English-language articles (n = 9), Level V publications (n = 19), in vitro studies (n = 118), and 102 studies not related to the topic were excluded. One reference was identified outside of PubMed. Thirty-eight references that met the inclusion criteria were identified from the original search. On the basis of our prepublication search, 2 other references were included. A total of 9 clinical and 31 preclinical studies were selected for further analysis. Of the clinical trials, 1 was classified as Level I, 2 as Level II, and 6 as Level IV. Eight referred to acellular scaffold implantation for partial meniscal replacement, and one comprised fibrin clot application. The mean modified Coleman Methodology score was 48.0 (SD, 15.7). Of the preclinical studies, 11 original works reported on studies using large animal models whereas 20 research studies used small animals. In these studies the experimental design favored cell-seeded scaffolds or scaffolds enhanced with growth factors (GFs) in attempts to improve tissue healing, as opposed to the plain acellular scaffolds that were predominant in clinical trials. Injection of mesenchymal stem cells and gene therapy are also presented as alternative strategies.

CONCLUSIONS:
Partial meniscal substitution using acellular scaffolds in selected patients with irreparable loss of tissue may be a safe and promising procedure. However, there is only 1 randomized controlled study supporting its application, and globally, many methodologic issues of published trials limit further conclusions. We registered a different trend in preclinical trials, with most considering augmentation of scaffolds by cells and/or GFs, as opposed to the predominantly acellular approach in clinical trials. Different TERM approaches to enhance meniscal repair or regeneration are in preclinical analysis, such as the use of mesenchymal stem cells, gene therapy, and GFs alone or in combination, and thus could be considered in the design of subsequent trials.

LEVEL OF EVIDENCE:
Level IV, systematic review of Level I to IV studies.

IORG Sports Medicine Update

Monday, October 31, 2011

Platelet-Rich Plasma Intra-Articular Injection Versus Hyaluronic Acid Viscosupplementation as Treatments for Cartilage Pathology: From Early Degeneration to Osteoarthritis.


Arthroscopy. 2011 Aug 8


Source

Biomechanics Laboratory-III Clinic, Rizzoli Orthopaedic Institute, Bologna, Italy.

Abstract

PURPOSE:

The aim of our study is to compare the efficacy of platelet-rich plasma (PRP) and viscosupplementation (hyaluronic acid [HA]) intra-articular injections for the treatment of knee cartilage degenerative lesions and osteoarthritis (OA).

METHODS:

The study involved 150 patients affected by cartilage degenerative lesions and early and severe OA. Fifty symptomatic patients were treated with 3 autologous PRP intra-articular injections and were evaluated prospectively at enrollment and at 2- and 6-month follow-up. The results obtained were compared with 2 homogeneous groups of patients treated with HA injections. One group was treated with injections of high-molecular weight HA; the other group was treated with low-molecular weight (LW) HA. International Knee Documentation Committee and EQ VAS scores were used for clinical evaluation; adverse events and patient satisfaction were also recorded.

RESULTS:

At 2 months' follow-up, the PRP and LW HA groups showed a similar improvement, with higher results compared with the high-molecular weight HA group (P < .005). At 6 months' follow-up, better results were observed in the PRP group (P < .005). PRP and LW HA treatments offered similar results in patients aged over 50 years and in the treatment of advanced OA. PRP showed a better performance compared with HA in younger patients affected by cartilage lesions or early OA.

CONCLUSIONS:

Autologous PRP injections showed more and longer efficacy than HA injections in reducing pain and symptoms and recovering articular function. Better results were achieved in younger and more active patients with a low degree of cartilage degeneration, whereas a worse outcome was obtained in more degenerated joints and in older patients, in whom results similar to those of viscosupplementation have been observed.

LEVEL OF EVIDENCE:

Level II, prospective comparative study.
IORG Sports medicine update

Friday, October 28, 2011

Single bundle anterior cruciate reconstruction does not restore normal knee kinematics at six months: An upright MRI study.

J Bone Joint Surg Br. 2011 Oct;93(10):1334-40.
Nicholson JASutherland AGSmith FW.


Abnormal knee kinematics following reconstruction of the anterior cruciate ligament may exist despite an apparent resolution of tibial laxity and functional benefit.
 We performed upright, weight-bearing MR scans of both knees in the sagittal plane at different angles of flexion to determine the kinematics of the knee following unilateral reconstruction (n = 12). The uninjured knee acted as a control. Scans were performed pre-operatively and at three and six months post-operatively. Anteroposterior tibial laxity was determined using an arthrometer and patient function by validated questionnaires before and after reconstruction. In all the knees with deficient anterior cruciate ligaments, the tibial plateau was displaced anteriorly and internally rotated relative to the femur when compared with the control contralateral knee, particularly in extension and early flexion (mean lateral compartment displacement: extension 7.9 mm (sd 4.8), p = 0.002 and 30° flexion 5.1 mm (sd 3.6), p = 0.004). In all ten patients underwent post-operative scans. Reconstruction reduced the subluxation of the lateral tibial plateau at three months, with resolution of anterior displacement in early flexion, but not in extension (p = 0.015). At six months, the reconstructed knee again showed anterior subluxation in both the lateral (mean: extension 4.2 mm (sd 4.2), p = 0.021 and 30° flexion 3.2 mm (sd 3.3), p = 0.024) and medial compartments (extension, p = 0.049). 
Our results show that despite improvement in laxity and functional benefit, abnormal knee kinematics remain at six months and actually deteriorate from three to six months following reconstruction of the anterior cruciate ligament.


IORG Sports Medicine Update 24th - 30th OCT 2011