II. Normal Joint Structures and Their Reaction to Injury

Neural and vascular anatomy of the menisci of the human knee

STUDY DESIGN

Review of literature.

OBJECTIVES

To review the general anatomy, vascular anatomy, healing potential, neural anatomy, and sensory functions of the menisci of the human knee.

BACKGROUND

Recent research has revealed important roles and functions of the menisci of the human knee.

METHODS AND MEASURES

A Medline search was performed using the following title and key words: menisci, meniscus, meniscal, vascular, blood, neural, nerve, anatomy, healing, sensory, mechanoreceptors, proprioception, nociceptors, surgery, meniscectomy, repair, and rehabilitation. The references from each article obtained were then reviewed in order to find additional articles not already located through the Medline search.

RESULTS

In adults, the blood supply to the menisci of the knee reaches the outer 10% to 33% of the body of the menisci. This portion of the menisci is capable of inflammation, repair, and remodeling. Neural innervation with nociceptors and type I, II, and III mechanoreceptors reaches the outer 66% of the body of the menisci. The anterior and posterior horns of the menisci have a rich supply of both blood vessels and nerves.

CONCLUSIONS

The menisci of the human knee are an important source of proprioceptive information regarding the position, direction, velocity, and acceleration and deceleration of the knee. Rehabilitation following injury or surgery to the menisci of the knee should, therefore, incorporate a proprioceptive retraining program that respects both the abilities and inabilities of different portions of the menisci to follow through with repair and remodeling.

The use of thermal agents to influence the effectiveness of a low-load prolonged stretch

This study was funded in part by a Minigrant award from California State University, Fresno. The use of thermal modalities to enhance stretching procedures is not well documented clinically. This study documented the effectiveness of applying superficial heat and cold in conjunction with a low-load prolonged stretch (LLPS) for increasing shoulder flexibility. Ninety-two healthy males were randomly assigned to one of five groups: 1) an LLPS alone, 2) heat applied in the initial phase of an LLPS, 3) cold applied in the final phase of stretch, 4) a combination of heat initially followed by cold, and 5) no intervention. Subjects received three, 40-minute treatments across a 5-day period. A follow-up measurement was taken 3 days later. Results demonstrated that an LLPS associated with the use of heat, ice, or a combination of both facilitated greater long-term improvements in flexibility compared with controls. However, only subjects receiving heat in the initial phase of an LLPS showed significant gains when compared with those who received stretching alone (p </= 0.05). We concluded that applying heat in conjunction with an LLPS to a nonpathologic shoulder is a clinically superior method of improving flexibility compared with an LLPS alone. J Orthop Sports Phys Ther 1992;16(5):200-207.