Hamstring Muscles: When it comes to the Hamstrings do not get Hamstrung….

By PetMassage | January 24, 2014 |

Full Title: Hamstring Muscles: When it comes to the Hamstrings do not get Hamstrung....

Author: Arlene Johnston

Date of Publication: January 24, 2014

PDF: http://petmassage.com/wp-content/uploads/Hamstring-Muscles-by-Arlene-Johnston-2014-01-24.pdf

Research Paper Text:

Abstract

The muscles in the hind limbs of dogs, called the hamstrings are a very powerful and essential group of muscles made up of striated or voluntary muscle fibers.

This paper will show what muscles are included in this group, called the hamstrings. Why is the group called the hamstrings, what actions these muscles have, their size, their sites of origin and insertion, the tendons and ligaments involved, and nerve and blood supplies involved in these very important muscles.

When it comes to the hamstrings do not get hamstrung……

The hamstrings got their name from the way European butchers would hook through these muscles, behind the knee, to hang up legs of slaughtered pigs in their shops to sell, hence the “ham” and the “stringing”. This also correlated to the battle fields of swordsmen, and in Roman times, and as a form of torture. In battle lacerating through these muscles of men, with their swords, or their steeds, they were rendered helpless, unable to move, and the pain and blood loss that occurred, provided an effective means of torture. In modern times the term “hamstrung” is used to describe the inability to move forward, with regards to thinking or application of a project for example.

The three main muscles of the hamstring group are the biceps femoris, semitendinous and semimembranous muscles (see figure1). There is also a fourth, less significant muscle of this group called the caudal crural abductor (see figure 2). This muscle is only present in carnivores and has the function to abduct the limb, with the origin being the sacrotuberous ligament and the insertion being the crural fascia (reference 1 ).

The hamstrings cover the caudal side of the thigh and are involved with many of the functions of the hind limb joints. They begin as high as the ischium and end as low as the tibia.

The main action of this group of muscles is to extend the hip joint (reference 1).

Biceps femoris.

The largest of the hamstrings is the femoral biceps; it is superficial covered only by the skin and fascia. The origin of the biceps femoris, the semitendinous and semimembranous is the ischial tuber and adjacent sacrotuberous ligament. The insertion point of the biceps is the patella and stifle ligaments, via the femoral and crural fascia. Tendons of the bicep also join tendons from the superficial digital flexor and gastocnemus to form the common calcanean tendon (see figure 2).The function of the biceps is the extension and abduction of the limb. It causes tarsal extension. The cranial part extends the hip and stifle, though the caudal part extends the hip but flexes the stifle (reference 3 and 4 )

Semitendinous.

The function of the semitendenous muscle is to extend the hip, stifle and tarsus when the foot makes contact with the ground, therefore propelling the dog forward. On a non-weight bearing leg it flexes the stifle and rotates the leg back and out. The origin for this muscle is the pelvic head and the insertion is the medial proximal tibia and a tendinous insertion on the calcaneal tuberosity, through joining the tendons from the superficial digital flexor and gastocnemius to form the common calcanean tendon (see figure 2), (references 3 and 4).

Semimembranous.

This is the most medial of the hamstring group and has the function to extend the hip and stifle in a weight bearing stance and on non-weight bearing limbs, it adducts and retracts the limb.

The origin of the semimembranous muscle, as with the other two hamstring muscles, is the pelvic head. The cranial insertion is onto the medial femoral condyle and the caudal is onto the medial tibial condyle (references 3 and 4)

Blood supply

The abdominal aorta ends by splitting into the internal and external iliac arteries. (see figure 3).

The internal iliac artery has a branch, the caudal gluteal (see figure 3), that serves the proximal hamstring muscles (reference 4).

The external iliac is the main artery of the hindlimb, it has a number of branches as it decends the limb, the branch which is the main server to the biceps femoris, semitendinous and semimembranous is the distal caudal femoris ( see figure 3).

The veins that return the blood up the hind limb coincide with the names of their arteries. The main veins that are connected to the hamstrings are, distal to proximal, the distal caudal femoral, to the femoral vein, to the external iliac and then into the caudal caval vein (see figure 3).

Nerve supply

The main nerve that serves the hamstrings is the sciatic nerve and its branches (see figure 4). The origin of the sciatic nerve is lumbar nerves L6 and L7 and sacral nerves S1 and S2. The sciatic nerve provides motor innervations to the femoral biceps, semitendinous and semimembranous muscle group. The sensory innervations from the sciatic nerve to the hamstrings are provided by way of the fibula and tibial branches of the sciatic.

Move forward and work those thigh muscles.

These large muscles are straightforward to find and feel on a dog and when healthy the muscles feel smooth with a consistent temperature. In a dog that is very active or that jumps/bounces allot, the hamstrings may feel enlarged or even look out of proportion due to their constant use, building the mass of the muscle. Hamstring muscles are used for all running and jumping activities and therefore can be susceptible to tearing and pulling just like human muscles.

A canine massage therapist can perform work on the hamstring muscles to help reduce the risk of common injuries. Massage can be done to prevent injuries, after an injury has occurred or after surgery to correct an issue. As with human muscle when injuries occur there is pain, inflammation and possible internal bleeding. Massage strokes, rocking and stretching can help address injuries and weaknesses in the muscles. The injured muscle may feel swollen and hot to the touch and the dog could express discomfort when the area is touched. Under the consult of a veterinarian, massage work can be done to reduce the inflammation, pain and discomfort of the dog.

Muscle strain is commonly seen in canine athletes that perform activities that result in sudden acceleration, turns, and jumping (http://acsma.org/wp-content/uploads/nl/sept_2012.pdf).

Keeping the hamstrings strong and flexible can reduce the risk of common injuries in dogs undertaking any exercise.

References

  1. http://en.wikivet.net/Hindlimb_-_Anatomy_%26_Physiology#The_Hamstrings
  2. http://acsma.org/wp-content/uploads/nl/sept_2012.pdf
  3. Anatomy of the dog (Google eBook) by Klaus Dieter Budras, Manson Publishing, Sep 13, 2007, page 129.
  4. Kainer, Robert A., DVM, MS and McCracken, Thomas O., MS. (2003) Dog anatomy, a coloring atlas. Plates 31, 33 and 34.

Anastasia’s Arf-irmation

By Anastasia Rudinger | January 23, 2014 |

My canine services are highly valued.

Mall massage: stranger in a strange land

By Jonathan Rudinger | January 23, 2014 |

I had a mall massage the other day. The gentleman who performed the massage was Chinese. He didn’t speak my language and I didn’t speak his. I understood from his motioning that he wanted me to hang my jacket on a hook on the wall, and he held up a plastic box for my shoes. He smiled and patted the table as an invitation. When I laid on the table, I assumed the position I usually would when I begin to receive a massage, face up. He got very agitated and, with the help of one of the other therapists, indicated that I was supposed to be prone. So I turned over. Then I was frantically made to understand that my head was at the wrong end of the table. So I got up, turned around (three times-no, not really) and positioned my body on his table, how and where I was supposed to.

The massage was given in an open room. So, of course I kept my clothes on. Working through my shirts and pants and socks there was no opportunity for him to feel any subtle reactions that my body might be signaling his touch. He pushed, shoved, squeezed, shook, stretched and slapped. His pace was rapid; his touch, strong and deliberate. He started at the head and ended at the feet. Whatever the he did on one side, he repeated on the other. His routine was set. He was obviously trained in his style of massage. I surmised that the session I got was the exact same session everyone gets.  

I noticed the aromas on his hands and breath. Intense kim chee! Great if you are dining out; not so much when you are trying to empty your mind. Relaxation is difficult when your eyes are crossed and you are gasping for air.   Could this give us a clue to how a dog experiences his sessions? A dog understands only a few words and phrases, and reads as much as he can into our body language. A dog moves, once he figures it out, where he is told to go and stays there until it is no longer comfortable (I stayed longer than I wanted). A dog observes all the patterns of pressures he feels. A dog is not only aware of smells, he responds viscerally to each and every aroma on our hands and breath. We’ve discussed in earlier “Helpful Hints” how dogs can even smell your thoughts.  

A dog on your table, like me in my mall massage, is also keenly aware of whether the signals his body is sending are being received, acknowledged and honored.  

Your dog need not be a stranger in a strange land, as I was in the mall, when he gets on your table.

Elevator Speech: Going up?

By Jonathan Rudinger | January 17, 2014 |

Before you start rolling your eyes … oops, too late … I wanted to share my perspective of creating an elevator speech with you. The name “Elevator Pitch” reflects the idea that it is possible to deliver the summary in the time span of an elevator ride, or approximately thirty seconds. The term itself comes from a scenario of an accidental meeting with someone important in the elevator. If the conversation inside the elevator in those few seconds is interesting and value adding, the conversation will continue after the elevator ride or end in the exchange of  a business card or a scheduled meeting.

The elevator sentence needs to be in your own words, and using terms and speaking style that is normal for you.
Use the speech as a way of defining to yourself what it is that you are doing and why you are doing it. It could be described as a mission or vision statement. In this scenario, the dreaded elevator speech is simply an affirmation, or a goal for a standard of performance that you set for yourself. Continue to edit and refine your speech until it says exactly and concisely what you want it to. 

Then, repeat it as a mantra, an affirmation, until your words become your reality. “Elevate” your awareness of who you are and the amazing things you do for dogs and their people.

Presence management

By Jonathan Rudinger | January 17, 2014 |

Every PetMassage session is unique. Each time you work on a dog, you are a different person. You are in a new time and place, having new thoughts, digesting new foods, in a new biorhythm. It is the same for the dog. Even if you’ve massaged her a thousand times before, she is still a uniquely evolving life form…just like you.

In a PetMassage, your new you connects with the latest and greatest version of the dog. The two of you share the experience, providing each of you an opportunity to support each other’s new lifestyle course correction.

Kids benefit from learning to massage dogs

By Jonathan Rudinger | January 17, 2014 |

The CDC reports that 4.5 million Americans are bitten by dogs each year, and one in five dog bites results in injuries that require medical attention. There are ways to make dog bites less likely and to help prevent children from being bitten by dogs.

When a child learns how to approach a dog, and how to respect the dog’s space, he or she will be less likely to get bitten. You can teach your child, or facilitate a workshop just like the one in the DVD, “PetMassage: A Kids Guide to Massaging Dogs.” The PetMassage for Kids program teaches children all over the world to interact safely and humanely with dogs. It has even been accepted as a skills merit patch with the Girl Scouts of America.

Greet the human first

By Jonathan Rudinger | January 17, 2014 |

This is from the PetMassage DVD titled, “Dog Handling in Canine Massage, Yoga Consciousness”. When the Pet Parent first brings a dog to you for a massage session, greet the human first briefly ignoring the dog. This gives power to the human. Then, accept the dog, immediately taking charge as alpha with your breath and body language.

Anastasia’s Arf-irmation

By Anastasia Rudinger | January 17, 2014 |

I wear a Buddha smile to lighten and brighten my life.

Touch receptors

By Jonathan Rudinger | January 17, 2014 |

How does a dog experience your touch? Dogs have touch receptors located in the skin. Their function is to activate senses: pressure, temperature, pain, and proprioception (a sense of where one’s limbs are). Each hair on a dog’s body has a receptor (known as mechanoreceptor) nerve at its base. The nose pad has high concentrations of sensory nerves, which are also found at the base of the vibrissae. The pads of the feet have sensory nerves which respond to vibration.

Toe talk

By Jonathan Rudinger | January 17, 2014 |

The direction that your toes are pointed affects how the dog is experiencing your presence. Feet pointed toward the dog are directly engaging. Feet angled away are less so. Feet pointed away and to the side will make fearful dogs more comfortable.