Veterinary technicians play major roles during surgical procedures as surgical assistants and circulating nurses. Important knowledge includes instrument identification, anatomical structures, and special needs of individual surgeries and surgeons. Surgeons’ preferences will dictate specific information such as patient positioning and special instrumentation. This chapter outlines many common and advanced surgical procedures based on their anatomical location. It includes conditions, causes, clinical signs, corrective procedures, positioning, special instrumentation, the surgical assistant’s role, and postoperative care. All patients require post-surgical monitoring, pain control, and perhaps some form of wound protection. Advanced procedures, more commonly performed in referral practices, are indicated with a star (*).
Definition: portion of medial coronoid process of ulna separates from parent bone
Cause: unknown but breed disposition (large breeds), inherited and environmental factors contribute to the condition, found in young dogs
Clinical signs: forelimb lame, worse after exercise, stiff after rest, often bilateral, elbow pain, and effusion
Diagnosis: radiographs or CT of elbows
Surgery*: arthroscopy or open approach to remove fragment (Figure 5.1).
Positioning: Dorsal recumbency for both arthroscopic and open repair
Special instrumentation:
Arthroscopic: Arthroscope 30° 1.9 or 2.4 mm scope, blunt(preferred)/sharp trocar, cannula, camera, arthroscopic hand instruments, ± motorized shaver, fluids, monitor, and tower
Open: Oschner (or other toothed) forceps, oscillating bone saw, battery or nitrogen tank to power saw, suction, bulb syringe, cautery
Assistant’s role:
Arthroscopic: Monitor fluid flow, manipulate limb for surgeon, set up arthroscope, set up motorized shaver if used.
Open: Assist with draping, set up suction/cautery, retract tissue with hand-held retractors, lavage field, suction field, set up bone saw, cut sutures.
Postoperative care: cryotherapy, restricted activity and physical rehabilitation
Figure 5.1 Radiograph of Left Fragmented Coronoid Process after removal.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Definition: Incomplete endochondral ossification causes cartilage to remain, fissure in this cartilage creates a flap that may loosen causing a “joint mouse”(Figure 5.2).
Cause: Unknown but breed disposition (large breeds), genetic, and dietary (over nutrition = rapid growth) factors contribute to condition, found in young dogs
Clinical signs: Forelimb lame (unilateral or bilateral), worse after exercise, stiff after rest, pain, and elbow effusion if osteoarthritis is present
Diagnosis: Radiographs of elbows
Surgery*: Arthroscopy or open approach to remove cartilage flap (Figures 5.3 and 5.4).
Positioning: Dorsal recumbency regardless of technique of repair
Definition: Anconeal process does not attach to proximal ulna
Cause: Center of ossification of the anconeous occurs separately from olecranon, disturbance of ossification of the juncture creates a fissure; large breed dogs, genetics, rapid growth, and trauma may contribute to condition
Clinical signs: Intermittent forelimb lame (unilateral), worse after exercise, stiff after rest, pain and elbow effusion, decreased elbow range of motion
Diagnosis: Radiographs (after five months of age) or CT scan of elbows (Figure 5.5).
Surgery*: Open approach to elbow to remove anconeal process or replacement with screw (Figure 5.6).
Positioning: Medial approach – dorsal recumbency; lateral approach – lateral recumbency with affected limb up
Special instrumentation: Gelpi self-retaining retractor, single action ronguer, oscillating saw if doing ulnar osteotomy, bone screws, screw placement instrumentation, power drill for lag screw placement
Assistant’s role: Assist with draping, suction during drilling, hydrate field during osteotomy, cut sutures, retract tissue if necessary
Postoperative care: No bandage or a soft padded bandage for up to 1 week, cryotherapy, restricted activity and physical rehabilitation
Definition: Inflammation of the biceps brachii tendon and its synovial sheath
Cause: Trauma to the biceps brachii (bicipital) tendon including recurring injury or overuse, may become mineralized or torn, often medium to large breeds and at least middle aged
Clinical signs: Unilateral forelimb lameness, may be progressive, pain on palpation of biceps tendon especially when shoulder is flexed and elbow is extended, patient is more lame if held in this position for two minutes.
Diagnosis: Radiographs of shoulders including skyline view ± arthrogram
Surgery: Arthroscopy* or open approach to shoulder to transect the biceps tendon or tenodesis to change origin of tendon (Figure 5.7).
Positioning: Arthroscopic – lateral recumbency with affected limb up; Open repair – dorsal recumbency
Special instrumentation:
Arthroscopy: Arthroscope, arthroscopy instrumentation, camera, monitor, and tower
Open repair: Gelpi self-retaining retractor, bone screws, bone screw placement instrumentation, power drill, suction, cautery
Assistant’s role: Retraction of tissue, lavage of field, suction, cut sutures.
Postoperative care: Velpeau sling for 2–3 weeks (open approach), cryotherapy, restricted activity, and physical rehabilitation after sling removal or after arthroscopy
Figure 5.7 Radiograph post bicep tendon tenodesis with screw placement.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Definition: Incomplete endochondral ossification causes cartilage to remain, fissure in this cartilage creates a flap that may loosen causing a “joint mouse”
Cause: Unknown but breed disposition (large breeds), genetic, and dietary (over nutrition = rapid growth) factors contribute to condition, found in young dogs
Clinical signs: Forelimb lame (unilateral or bilateral), worse after exercise, improves with rest, pain on full shoulder extension
Diagnosis: Radiographs of shoulders or CT scan (Figure 5.8).
Surgery: Arthroscopy* or open approach to remove cartilage flap
Positioning: Dorsal recumbency for lateral approach
Special instrumentation:
Arthroscopy – Arthroscope, arthroscopy instrumentation, camera, monitor, and tower
Open: Oschner forceps or other toothed forceps, bone curette suction, cautery, self-retaining retractor (Gelpi) (Figure 5.9).
Assistant’s role:
Arthroscopic : Monitor fluid flow, manipulate limb, set up arthroscope
Open: Retraction of tissue, suction, cut sutures
Postoperative care: Cryotherapy, restricted activity, and physical rehabilitation
Diagnosis: Not evident on imaging, physical exam findings
Surgery*: Conservative treatment first, if not successful: arthroscopic or open approach to shoulder to place bone anchors and suture to stabilize shoulder
Positioning: Lateral recumbency with affected limb up for arthroscopy; dorsal recumbency for medial approach for open repair
Special instrumentation:
Arthroscopy: Arthroscope, arthroscopy instrumentation, camera, monitor and tower
Open: Gelpi self-retaining retractor, bone anchors, bone screws, bone screw placement instrumentation, large size monofilament nonabsorbable suture, suction, cautery
Assistant’s role:
Arthroscopic: Manipulation of limb, monitor fluid flow, set up arthroscope
Open: Suction field, hydrate tissues, stabilize limb for screw placement, hand screw placement instrumentation in correct order
Definition: Partial or complete tearing of the cranial cruciate ligament
Cause: Thought to be related to chronic inflammation of the cranial cruciate ligament (CCL) causing long-term deterioration and eventual tearing, (Muir 2010) most common in large breed dogs, may have a genetic component (Wilke 2010)
Clinical signs: Acute to chronic grade 2–5/5 rear leg lameness, stifle effusion, painful during stifle manipulation, may sit to one side with affected leg in extension
Diagnosis: Positive cranial drawer test, positive tibial thrust test, radiographs to assess degree of inflammation, and degenerative joint disease
Surgery:
Extracapsular repair, Lateral fabellar suture, “Fishing line” technique, (Schulz 2007c; Cook 2010) – stabilization of the stifle via suture outside the joint, suture material is monofilament nylon
Surgery: Using heavy monofilament suture/ leader line, a cruciate needle is passed around the fabella. Next, the suture is passed behind the patellar ligament. A hole is drilled through the tibial crest. With the stifle flexed the sutures is passed through the hole and tied or crimped. routine closure (Figure 5.11).
Positioning: Lateral or dorsal recumbency
Special instrumentation: Fishing or leader line, braided orthopedic suture, large monofilament nonabsorbable suture, suction, cautery, cruciate needle, metal crimper pieces, crimper tool
Assistant’s role: Stabilize the limb, suction field, provide hemostasis, cut sutures
Postoperative care: Restricted activity for 8–10 weeks, physical rehabilitation to improve joint mobility and increase muscle strength
Tibial plateau leveling osteotomy* (TPLO) – mechanical stabilization of the stifle via a bone cutting procedure to change the tibial plateau angle, TPLO limits the shear force created by the compression of the stifle when weight-bearing and thus reducing tibial thrust (Milovancev and Schaefer 2010)
Surgery: A medial approach to the joint provides visualization of the joint to allow for the bone saw to cut the tibia. As the osteotomy is completed the tibial plateau slope decreases, which allows for a more neutral or caudal cranial cruciate thrust. A TPLO bone plate is placed to stabilize the osteotomy site (Figures 5.12 and 5.13).
Positioning: Dorsal recumbency or dorso-lateral oblique, tilted toward the affected limb, to allow the limb to lay flat on the surgery table top
Special instrumentation: TPLO instrument set (including torque limiter, radial saw blades, jig), TPLO bone plate set, bone screw set (locking or non-locking), bone saw, bone drill, Gelpi self-retaining retractor (Figure 5.14).
Assistant’s role: Stabilize limb for sawing and/or drilling of screw holes, drill screw holes, place/remove k-wires/pins, retraction of patellar tendon during osteotomy, suction, hydrate field, cut sutures
Postoperative care: Restricted activity for 8–10 weeks until radiographs show bony healing, physical rehabilitation to improve joint mobility and increase muscle strength (Figure 5.15).
Tibial tuberosity advancement* (TTA) – mechanical stabilization of the stifle via a bone cutting procedure to neutralize cranial tibiofemoral shear force (Boudrieau 2010)
Surgery: Using an open approach to the stifle joint a partial tibial crest osteotomy is performed. A “cage” is secured with bone screws to keep the osteotomy site open. A TTA bone plate is used to stabilize the osteotomy site.
Positioning: Dorsal recumbency or dorso-lateral oblique, tilted toward the affected limb, to allow the limb to lay flat on the surgery table top
Special instrumentation: TTA implant set, power saw, periosteal elevator, TTA instrumentation set, Gelpi self-retaining retractor (Figure 5.16).
Assistant’s role: Stabilize limb, suction, cut sutures, hold plate while first screw holes being drilled
Postoperative care: Restricted activity for 8–10 weeks, physical rehabilitation to improve joint mobility and increase muscle strength (Figure 5.17).
Tightrope® – Stabilization of the stifle via suture technique outside the joint, suture material is braided fiber wire
Surgery: An ultra-high strength, braided synthetic ligament is passed through bone tunnels created in the distal femur and proximal tibia. The “ligament” is pulled tight and secured with a femoral button, simulating the normal cranial cruciate ligament.
Positioning: Dorsal recumbency
Special instrumentation: Power drill, drill bit, hand chuck, pin, ligament graft, femoral button, Gelpi retractor, suction cautery
Assistant’s role: Stabilize limb while tunnels created, suction, cut suture, stabilization of leg as graft is tightened
Postoperative care: Restricted activity for 8–10 weeks, physical rehabilitation to improve joint mobility and increase muscle strength
Figure 5.11 Leader line knotted for extra-capsular repair.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Figure 5.12 Using saw for Tibial Plateau Leveling Osteotomy (TPLO). Note: Assistant dripping fluid on bone to cool it while sawing.
Figure 5.13 Drilling screw hole for placement of TPLO plate.
Definition: Displacement of the patella, either medially or laterally
Cause: Congenital condition, medial luxation is most common, widespread in toy and miniature breeds but also occurs in large breeds and cats, bilateral complaint in 20–25% of patients
Clinical signs: Intermittent to continual non-weight bearing lame on affected leg, divided into the following grades:
Patella easily luxates, is easily reduced, spends most of the time in correct position (surgery generally not indicated)
More frequent luxation than grade one, patella is easily reduced and most often in the correct position (may or may not require surgery)
Patella always luxated, reducible with effort (requires surgical correction)
Patella always luxated, not reducible (requires surgical correction)
Surgery: A variety of surgeries correct this condition, they may be used singularly or in combination. The trochlear groove is deepened with a trochlear wedge, block recession or trochlear resection procedure. Additional procedures may be done to maintain placement of the patella in the newly created groove: Overlap of lateral or medial retinaculum, fascia lata overlap, patellar and tibial antirotational suture ligament, desmotomy and partial capsulectomy, quadriceps release, tibial tuberosity transposition (TTT) along with osteotomies if femoral deformities are present (Figure 5.18).
Positioning: Dorsal recumbency
Special instrumentation: Bone saw, number 20 blade, osteotome, mallet, ronguer, k-wires, power drill, self-retaining retractor, suction, cautery
Assistant’s role: Stabilize limb, suction site if bone saw used, lavage field, cut sutures
Postoperative care: Restricted activity for 4 weeks, physical rehabilitation to improve joint mobility and increase muscle strength, encourage weight bearing, sling support under abdomen to assist walking if bilateral procedure (Figure 5.20).
Figure 5.19 Cranial-caudal radiographic view of medial patellar luxation – pre op.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Figure 5.18 Cutting wedge for repair of MPL (medial patellar luxation).
Figure 5.20 Cranial-caudal radiographic view of corrected medial patellar luxation – post op.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Diagnosis: Radiographs, positive Ortolani sign (young, sedated patient), painful hip range of motion, crepitus in older patients (Figure 5.21).
Surgery: Conservative therapy consisting of exercise modification, medical, and dietary management may be indicated pending the severity of the patient’s clinical symptoms. The type of surgical procedure is dependent upon the age of the patient, clinical severity, and the client’s expectations. For example, a performance or working dog may have a better outcome and greater return to function with a total hip replacement than with a femoral head ostectomy.
Femoral head ostectomy (FHO) or Femoral head and neck excision (FHNE) (Piermattei et al. 2006c) – removal of the head and neck of the femur to create a fibrous false joint to relieve pain from bone on bone contact, surgery is a salvage procedure for end-stage degenerative joint disease (may also be performed following femoral head/neck fractures or acetabular fractures).
Surgery: A craniolateral approach to the hip is made to allow intentional luxation of the hip. The round ligament is incised (if still intact) and the femoral head is subluxated. The head and neck is then be excised.
Positioning: Lateral recumbency with affected limb up
Special instrumentation: Power saw, osteotome, mallet, ronguer, rasp, suction, cautery, Gelpi self-retaining retractor, lavage fluid
Assistant’s role: Lavage field, drip saline on bone as osteotomy is performed, cut sutures, rotate/stabilize limb, load saw blade on power saw
Postoperative care: Restricted activity for two weeks, then encourage limb use, physical rehabilitation to improve joint mobility and increase muscle strength (Figure 5.22).
Juvenile pubic symphysiodesis (JPS) (Piermattei et al. 2006d) – pubic bone physis closure via stapling or electrocautery causing improvement in the acetabular angle and thus more coverage of the femoral head by the acetabulum, degenerative joint disease (DJD) prevention, performed at 12–16 weeks of age. PennHIP® radiographs determine a distraction index (DI) – if DI is greater than or equal to 0.70, surgery is not effective in preventing DJD (Dueland et al. 2010).
Surgery: A ventral midline incision over the pubis allows dissection/retraction of muscle to expose pubic symphysis. Cautery is set at 40 watts and ablation is performed every 2–3 mm along pubic symphysis
Positioning: Dorsal recumbency
Special instrumentation: Small malleable retractor, suction, cautery
Assistant’s role: Retraction of muscle, suction, cut sutures
Postoperative care: Moderate exercise for 2–3 months
Total hip replacement/Arthroplasty* (THR/THA) (Piermattei et al. 2006e) – removal of the femoral head/neck and replacement with a stainless steel or titanium head/stem as well as reaming of the acetabulum and replacing it with a high-density polyethylene cup, surgery is a salvage procedure for end-stage degenerative joint disease (also may be performed for femoral head/neck fractures) (Figure 5.23).
Surgery: A craniolateral approach is made to the hip. The hip is luxated and the round ligament is incised. The femoral head and neck are excised. The femoral canal is broached and prepped for implant placement. The acetabulum is reamed and prepped for acetabular placement. After implant placement the hip is repositioned, range of motion is evaluated prior to closure.
Positioning: Lateral recumbency with surgical hip up, use THA positioner may be used to insure pelvic alignment (Figure 5.24).
Special instrumentation: Cemented/cementless femoral prosthesis, femoral head implant, acetabular implant, power saw/drill, total hip instrumentation set, Gelpi self-retaining retractor, deep muscle retractor (Myerding), cement (if needed), evacuation bowl, Hohmann retractors, suction, cautery, lavage fluid (Figures 5.25 and 5.26).
Assistant’s role: Strict enforcement of asepsis, mix cement, muscle retraction, stabilize limb, hand instruments during joint prep in correct order, keep instruments clean between use, cut sutures
Postoperative care: Very restricted activity for four weeks, use of sling for walking at all times to avoid slipping and luxation of implants, rehabilitation starting 2–4 weeks postoperative, slow increase in activity after 4–8 weeks
Triple/double pelvic osteotomy* (TPO/DPO) (Piermattei et al. 2006f) – cuts made in the ilium and pubis (DPO) as well as ischium (TPO) to allow rotation of the acetabulum and provide more coverage of the femoral head, performed only in skeletally immature dogs (4–12 months) without degenerative changes, reduces degenerative joint disease from hip dysplasia (Figure 5.27).
Surgery: An incision is made over the pectinius muscle to allow dissection and access to pubis. An osteotomy is performed on the medial wall of the acetabulum. The incision is closed. An ischial approach is made and the ischial osteotomy is performed. The ischial osteotomy is centered over the obturator foramen. Finally the ilial approach and osteotomy is performed. The pelvis is realigned to permit the application of a bone plate to stabilize the pelvis.
Positioning: Dorsal recumbency/lateral recumbency with affected hip up *Note: Re-positioning of patient may be necessary to allow access to pelvic osteotomy sites*
Special instrumentation: Power bone saw, bone plates, bone screws, bone screw placement instrumentation, osteotome, mallet, bone holding forceps, Gelpi self-retaining retractors, Hohmann retractors, periosteal elevator, second set of drapes, instruments ( if repositioning of patient is necessary to access pelvic osteotomy sites)
Assistant’s role: Suction during osteotomies, lavage field as osteotomy performed, muscle retraction, handing of screw placement instruments in proper order when screws are being placed, cut sutures
Postoperative care: Exercise restriction for 4–6 weeks, physical rehabilitation, sling walk when on slippery surfaces (Figure 5.28).
Figure 5.21 Ventral-dorsal radiographic view of dysplastic hips.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Figure 5.22 Post op ventral-dorsal radiographic view of hips post femoral head osteotomy (FHO).
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
Figure 5.23 Post op VD view of total hip arthroplasty (THA) implants.
(Paul Manley, University of Wisconsin, Madison, WI. Reproduced with permission from Paul Manley.)
