CCAT - Certified Companion Animal Rehabilitation Therapist Canine Anatomy and Biomechanics Questions and Answers — Questions and Answers
Question 1: A 7-year-old Labrador Retriever presents with chronic, low-grade lameness of the right pelvic limb. The owner notes the dog is reluctant to jump into the car and often sits with its right leg abducted. Palpation reveals pain and instability over the dorsal aspect of the pelvis. Which joint is most likely affected, given its primary role in transferring propulsive forces from the pelvic limbs to the axial skeleton?
- Coxofemoral joint
- Lumbosacral joint
- Sacroiliac joint (Correct answer)
- Stifle joint
Correct answer: Sacroiliac joint
The sacroiliac (SI) joint is responsible for transferring the forces generated by the hind limbs to the spine. Dysfunction in this joint, often subtle, can lead to signs like reluctance to jump, pain on palpation over the area, and compensatory postures like sitting with the affected leg out to the side.
Question 2: During a biomechanical gait analysis of a dog at a trot, which of the following patterns of limb movement is considered normal and most efficient?
- Ipsilateral limbs (right front and right rear) move together.
- Diagonal limbs (right front and left rear) move together. (Correct answer)
- All four limbs have a moment of suspension simultaneously.
- Three feet are in contact with the ground at all times.
Correct answer: Diagonal limbs (right front and left rear) move together.
The trot is a symmetrical, two-beat diagonal gait where diagonal pairs of limbs move forward at the same time with a moment of suspension between each step. This gait is often used to evaluate lameness because the limbs are not assisted by the contralateral side.
Question 3: Which of the following muscles acts as a primary flexor of the shoulder joint and also pulls the thoracic limb caudally, playing a significant role in propulsion?
- Supraspinatus
- Brachiocephalicus
- Latissimus dorsi (Correct answer)
- Pectoralis profundus
Correct answer: Latissimus dorsi
The latissimus dorsi is a large, triangular muscle that originates from the thoracolumbar fascia and inserts on the humerus. Its primary actions are to flex the shoulder joint and draw the limb caudally, making it a powerful muscle for propulsion.
Question 4: A canine patient recovering from a cranial cruciate ligament (CCL) repair surgery is beginning rehabilitation. To specifically promote active stifle flexion and extension, which of the following exercises would be most appropriate in the early stages of recovery?
- Cavaletti rails set at maximum height
- Uncontrolled off-leash running in a large field
- Weaving through poles at a fast pace
- Controlled sit-to-stand exercises (Correct answer)
Correct answer: Controlled sit-to-stand exercises
Sit-to-stand exercises are a controlled way to increase active range of motion in the stifle joint. The sitting motion promotes flexion, while the standing motion promotes extension. This exercise helps to rebuild hindlimb strength and can be easily modified to the patient's tolerance.
Question 5: The canine carpus (wrist) is a complex structure. The majority of its flexion and extension occurs at which specific joint?
- Middle carpal joint
- Carpometacarpal joint
- Antebrachiocarpal joint (Correct answer)
- Intercarpal joints
Correct answer: Antebrachiocarpal joint
The antebrachiocarpal joint, the articulation between the radius/ulna and the proximal row of carpal bones, is responsible for the vast majority (approximately 70%) of the total range of motion in the carpus. The middle carpal and carpometacarpal joints have minimal movement.
Question 6: In the canine pelvic limb, the large sesamoid bone embedded in the quadriceps femoris tendon that articulates with the femur is known as the:
- Calcaneus
- Fabella
- Talus
- Patella (Correct answer)
Correct answer: Patella
The patella, or kneecap, is the largest sesamoid bone in the dog's body. It is located within the tendon of the quadriceps femoris muscle and articulates with the trochlear groove of the femur, playing a crucial role in the biomechanics of the stifle (knee) joint.
