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Key Techniques in Orthopaedic Surgery

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osteoarthritis unless there
is a significant mechanical component causing the
patient symptoms.
Contraindications
1. Unsatisfactory skin condition
2. History of knee reflex sympathetic dystrophy 
(relative)
Preoperative Preparation
1. Knee radiographs
2. Magnetic resonance imaging (MRI) depending on
the patient’s symptoms and the specific surgical
procedure planned
Special Instruments, Position, 
and Anesthesia
1. The patient is placed supine on the operating room
table.
2. All pressure points should be padded.
3. The procedure can be done with general, spinal, or
local anesthesia with sedation.
4. A leg holder or lateral support post can be used.
5. A pneumatic thigh tourniquet should be placed as
proximal as possible on the thigh. However, most
standard arthroscopic procedures can successfully
be completed without tourniquet inflation.
6. Standard arthroscopic instruments are needed.
These should include an arthroscopic “shaver.”
7. If a meniscal repair is contemplated, the instru-
ments and implants for introduction of an absorbable
fixation device should be available.
Tips and Pearls
1. Arthroscopy is most reliable for symptomatic
mechanical problems within the knee such as
meniscal tears and loose bodies. The results
achieved with articular cartilage debridement for
patellofemoral syndrome (“chondromalacia”) or
osteoarthritis or with menisectomy for asympto-
matic or incidental meniscal tears are significantly
less predictable. The best results occur when the
patient’s preoperative symptoms and physical exam-
ination correlate with mechanical finding on a
diagnostic study (i.e., MRI).
2. If a leg holder is utilized it should be positioned as
proximal as possible on the thigh. If a lateral sup-
port post is utilized, it should be positioned just dis-
tal to the tourniquet on the proximal thigh.
3. In general, all procedures should commence with a
systematic diagnostic inspection of the entire joint
performed in a standard manner prior to any oper-
ative surgery. However, if a loose body is found, it is
appropriate (and desirable) to immediately proceed
with its removal while it is easily visualized. The
author’s preferred order for the systematic diagnos-
tic inspection of the entire knee joint is: suprapatel-
lar pouch, patellofemoral joint, lateral gutter, medial
gutter, medial compartment, intercondylar notch,
and lateral compartment.
4. Add epinephrine to the inflow bags to minimize
bleeding.
5. Remember the arthroscope and camera move inde-
pendently. The arthroscope should be positioned
and rotated to optimize the field of view. The cam-
era should then be rotated to insure correct picture
orientation on the video monitor. The light cord
inserts on the arthroscope 180 degrees from the
scope’s field of view (Fig. 24–2).
What To Avoid
1. Try to avoid multiple operations on the same knee
for the same problem over a short time period.
2. Avoid violating the patella tendon with placement
of the portals.
3. Attempt to minimize damage to the articular carti-
lage with the arthroscopic instruments and shavers.
4. Avoid leaving free meniscal debris floating within
the joint after morselization of the meniscus.
Postoperative Care Issues
1. Consider injecting a local anesthetic (i.e., 0.25%
bupivacaine) into the knee at the end of the proce-
dure to minimize postoperative pain.
2. A compressive dressing should be placed at the end
of surgery and is normally removed approximately
48 hours after the procedure.
3. In most cases, patients can weight-bear as tolerated
(WBAT) after surgery. Most patients are able to dis-
continue crutches in the first week after surgery.
4. Range-of-motion and strengthening exercises can
be initiated immediately after the procedure. Routine
formal physical therapy is not required for all pa-
tients. Most patients can successfully rehabilitate
with a home exercise program.
Operative Technique
Arthroscope insertion
1. Position the patient supine on the operating room
table. Place a thigh tourniquet as proximal as possi-
ble on the thigh. While most cases can be per-
formed without tourniquet inflation, the tourniquet
can be inflated if bleeding impedes visualization.
2. Depending on surgeon preference, either a post or
thigh holder can be used. Position the lateral post
just distal to the thigh tourniquet. If a thigh holder
is utilized, position it as proximal as possible.
3. Prepare and drape the limb in the hospital’s stan-
dard sterile fashion.
4. Extend the knee and make a small stab wound supe-
rior and medial to the patellar. Ideally this should
be medial to the quadriceps tendon (Fig. 24–1).
5. Introduce the inflow cannula into the joint utiliz-
ing the blunt obturator. Commonly, a “pop” can be
felt as the obturator enters the knee capsule. Do not
inflate the joint at this time, since the fluid will
obscure the landmarks used in placement of the
remaining portals.
6. Flex the knee. Identify the “soft spot” for the infe-
rior lateral portal. This can be palpated as a soft
indentation in the lateral retinaculum which lies
just lateral to the patellar tendon at the level of the
joint line. Many surgeons use the inferior pole of
the patellar as a landmark. Make a small stab inci-
sion in this spot (the author prefers a horizontal
incision). Inflate the joint (Fig. 24–1).
7. Introduce the cannula for the arthroscope through
this portal. This is best done with the knee still
1 6 0 K N E E A N D L E G
1 6 1
Inflow
Instrument
Arthroscope
Arthroscope
Light cord
Focus
Camera
Outflow Camera optic
Light cord
Inflow
Figure 24–1 Standard arthroscopy portals. The
inflow is positioned superior and medial to 
the patella. The arthroscope is placed in the
inferior-lateral portal while the inferior-medial
portal is used for instruments.
Figure 24–2 Arthroscope. Note the components of a common
arthroscopic setup. The arthroscope is introduced into the joint 
through a cannula that allows either fluid outflow (pictured) or 
inflow. The arthroscope and camera rotate independently. The light
cord inserts on the arthroscope 180 degrees from the scope’s field 
of view.
Figure 24–3 Medial compartment. Note the
standard position for viewing the medial
compartment. The knee is either extended or
slightly flexed. The arthroscope is positioned 
in the medial compartment so it parallels the 
joint line and looks lateral (light cord is parallel 
to the joint line and going medial). The camera is
adjusted so the picture is correctly oriented with
the femur superior and the tibia inferior. A valgus
stress can be applied to the tibia to “open” the
medial compartment and improve visualization.
1 6 2
MFC
Tibial plateau
Normal anterior
cruciate ligament
Tibial plateau
Torn ACL
LFC
MFC
Medial meniscal tear
LFC
MFC
Normal meniscus
A
B
C
D
A
Figure 24–4 (A) Standard medial compartment
view. The camera is adjusted so the picture is
correctly oriented with the femur superior and
the tibia inferior. This allows visualization of 
the medial femoral condyle (MFC), medial 
tibial plateau (MTP), and medial meniscus. 
(B) Standard intercondylar notch view.The
camera is adjusted so the picture is correctly
oriented with the femur superior and the tibia
inferior. This allows visualization of the medial
femoral condyle (MFC), lateral femoral condyle
(LFC), and anterior cruciate ligament (ACL). 
(C) Medial meniscal tear (radial). Note the medial
femoral condyle (MFC), medial tibial plateau
(MTP), and medial meniscus. A radial tear of 
the medial meniscus is depicted. (D) Anterior
cruciate ligament (ACL) tear. Note the medial
femoral condyle (MFC), lateral femoral condyle
(LFC), and anterior cruciate ligament (ACL). 
A tear of the ACL is depicted.
Figure 24–5 (A) “Figure four”