Chapter 8
Joints
275
earlier that disappeared as suddenly as it had come. Her diagnosis
was arthritis. (a) What type? (b) What is the precipitating cause of
this particular type of arthritis?
4.
Grace heard on the evening TV news that the deer population
in her state had been increasing rapidly in the past few years and
it was common knowledge that deer walked the streets at night.
AFer the program, she suddenly exclaimed, “So that’s why those
three boys in my son’s class got Lyme disease last year.” Explain
what she meant by that comment.
5.
Tony Bowers, an exhausted biology student, was attending a
lecture. AFer 30 minutes or so, he lost interest and began to doze.
As the lecture ended, the hubbub aroused him and he let go with
a tremendous yawn. To his great distress, he couldn’t close his
mouth—his lower jaw was “stuck” open. What do you think had
happened?
2.
As Harry was running down the road, he tripped and his leF
ankle twisted violently to the side. When he picked himself up,
he was unable to put any weight on that ankle. ±e diagnosis was
severe dislocation and sprains of the leF ankle. ±e orthopedic
surgeon stated that she would perform a closed reduction of the
dislocation and attempt ligament repair by using arthroscopy.
(a) Is the ankle joint normally a stable joint? (b) What does its
stability depend on? (c) What is a closed reduction?
(d) Why is ligament repair necessary? (e) What does arthroscopy
entail? (f) How will the use of this procedure minimize Harry’s
recuperation time (and suffering)?
3.
Mrs. Bell, a 45-year-old woman, appeared at her physician’s office
complaining of unbearable pain in the interphalangeal joint of
her right great toe. ±e joint was red and swollen. When asked
about previous episodes, she recalled a similar attack two years
Related Clinical Terms
Ankylosing spondylitis
(ang
9
kĭ-lōz
0
ing spon
0
dĭ-li
9
tis;
ankyl
5
crooked, bent;
spondyl
5
vertebra) A variant of rheumatoid
arthritis that chiefly affects males; it usually begins in the
sacroiliac joints and progresses superiorly along the spine. ±e
vertebrae become interconnected by fibrous tissue, causing the
spine to become rigid (“poker back”).
Arthrology
(ar-throl
9
o-je;
logos
5
study) ±e study of joints.
Arthroplasty
(“joint reforming”) Replacing a diseased joint with an
artificial joint.
Chondromalacia patellae
(kon-dro-mal-a
9
sĭ-ah; “soFening of
cartilage by the patella”) Damage and soFening of the articular
cartilages on the posterior patellar surface and the anterior
surface of the distal femur; most oFen seen in adolescent
athletes. Produces a sharp pain in the knee when the leg is
extended (in climbing stairs, for example). May result when the
quadriceps femoris, the main group of muscles on the anterior
thigh, pulls unevenly on the patella, persistently rubbing it
against the femur in the knee joint; oFen corrected by exercises
that strengthen weakened parts of the quadriceps muscles.
Rheumatism
A term used by laypeople to indicate disease involving
muscle or joint pain; consequently may be used to apply to
arthritis, bursitis, etc.
Synovitis
(sin
0
o-vi
9
tis) Inflammation of the synovial membrane of
a joint. Caused by injury, infection, or arthritis. Excess synovial
fluid accumulates in the joint cavity, a condition called
effusion
that causes the joint to swell, limiting joint movement.
AT T H E C L I N I C
In the previous chapter, you met
Kayla Tanner, a 45-year-old mother of
four who suffered a dislocated right
hip in the bus accident on Route 91.
Prior to the closed reduction, the doctors noted that her right
thigh was flexed at the hip, adducted, and medially rotated.
After the reduction, the hip was put through a gentle range of
motion (ROM) to assess the joint. A widened joint space in the
postreduction X ray showed that the reduction was not complete,
but no bone fragments were visible in the joint space. Mrs. Tanner
was scheduled for immediate surgery.
The surgeons discovered that the acetabular labrum was
detached from the rim of the acetabulum and was lying deep
within the joint space. The detached portion of the labrum was
excised, and the hip was surgically reduced. During the early
healing phase (first two weeks), Mrs. Tanner was kept in traction
with the hip abducted.
1.
Joints can be classified by structure and by function. How would
you structurally and functionally classify the joint involved in the
injury in this case?
2.
Name the six distinguishing features that define the structural
classification of the joint involved in this injury.
3.
The doctors noted that there were no bone fragments in the
joint space. What is normally found in this space?
4.
Surgeons had to remove a portion of Mrs. Tanner’s acetabular
labrum. What is this structure and what function does it supply
at this joint?
5.
The doctors noted that Mrs. Tanner’s thigh was flexed at the
hip, adducted, and medially rotated. Describe what this means
in terms of the position of her leg.
6.
Hip dislocations can be classified as anterior or posterior
depending on which direction the head of the femur is facing
after it dislocates. Based on the description you provided in
question 5, which type of dislocation did Mrs. Tanner suffer?
7.
In order to assess the joint as part of Mrs. Tanner’s
rehabilitation, clinicians would want to assess all of the
movements that normally occur at the hip. List all the
movements that the clinicians will need to assess.
(Answers in Appendix H)
Case Study
Joints
8
previous page 309 Human Anatomy and Physiology (9th ed ) 2012 read online next page 311 Human Anatomy and Physiology (9th ed ) 2012 read online Home Toggle text on/off