title: Neuromuscular recovery after medial collateral ligament disruption and eccentric rehabilitation program.
abstract: OBJECTIVE
  Medial collateral ligament (MCL) rupture of the knee joint frequently occurs during sport activities. However, the optimal rehabilitation strategy after such lesion is unknown. The aim of this study was to assess the effects of progressive eccentric rehabilitation program on neuromuscular deficits induced by MCL transection.
  
  
  METHODS
  Rats were randomized as follows: (i) control group (C, n = 10) without any surgery; (ii) lesion groups in which neuromuscular measurements were made 1 (L1, n = 10) and 3 wk (L3, n = 9) after MCL transection by a 15- to 20-min surgery (this group was designed to determine changes induced by the MCL transection); and (iii) eccentric group (ECC, n = 7) in which rats performed a progressive 2-wk eccentric rehabilitation program beginning 1 wk after MCL transection surgery. Dynamic functional assessments were performed at weeks 1 and 3 after the MCL transection by measuring the maximal and minimal knee angles during the stance phase of the gait cycle. Neuromuscular measurements included 1) modulation of H-reflex in response to a 10-mM KCl injection, 2) analysis of the twitch relaxation properties of the quadriceps muscle, and 3) recording of metabosensitive and mechanosensitive afferents activity in response to chemical injections and to tendon patellar vibrations, respectively.
  
  
  RESULTS
  Our results indicated that H-reflex modulation induced by metabosensitive afferents was disturbed by MCL transection without any recovery despite rehabilitation program. Responses of both metabosensitive and mechanosensitive muscle afferents, as well as the muscle relaxation properties, were fully recovered after the eccentric rehabilitation program.
  
  
  CONCLUSIONS
  Our results directly indicated an influence of progressive eccentric program on muscle afferents response after MCL section but apparently not for spinal reflex modulation.
authors.affiliation: UMR CNRS 6233, Institut des Sciences du Mouvement, Etienne-Jules Marey, Equipe Plasticité des Systèmes Nerveux et Musculaire, Université de la Méditerranée, Aix-Marseille II - Aix-Marseille Université, Faculté des Sciences du Sport, Parc Scientifique et Technologique de Luminy, Marseille, FRANCE.
authors.forename: Jérôme
authors.initials: J
authors.lastname: Laurin
authors.forename: Erick
authors.initials: E
authors.lastname: Dousset
authors.forename: Serge
authors.initials: S
authors.lastname: Mesure
authors.forename: Patrick
authors.initials: P
authors.lastname: Decherchi
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004558:Electric Stimulation; D005260:Female; D006181:H-Reflex / Q000502:physiology; D006614:Hindlimb / Q000502:physiology; D007718:Knee Injuries / Q000534:rehabilitation*; D019344:Lactic Acid / Q000494:pharmacology; D017888:Medial Collateral Ligament, Knee / Q000293:injuries*; D009119:Muscle Contraction / Q000502:physiology; D009475:Neurons, Afferent / Q000502:physiology*; D017847:Patellar Ligament / Q000502:physiology; D010805:Physical Conditioning, Animal; D011189:Potassium Chloride / Q000494:pharmacology; D052097:Quadriceps Muscle / Q000294:innervation* / Q000502:physiology; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D020127:Recovery of Function / Q000502:physiology*; D014732:Vibration
chemical_list: D019344:Lactic Acid; D011189:Potassium Chloride