MSK 4 Ligaments Tendons Flashcards
What are the three parts of the Calcaneal tendon?
- Gastrocnemius – paired tendons
- Combined tendon of the Semitendinosis, gracilus and biceps femoris m.
- Superficial digital flexor m.
What are the clinical signs of a full rupture of the Calcaneal tendon?
- Sudden severe pelvic limb lameness
- Plantigrade stance
- Hyperflexed stifle/hock
- May not be painful to palpate
- Possible laceration or bruise swelling over the area
What are the clinical signs of a partial rupture of the Calcaneal tendon?
- Digits flexed
- Partial plantigrade stance
- Painful and swollen
- History of chronic lameness that worsens
What are the ideal properties of suture to repair tendons?
- Long absorbing or non-absorbing monofilament
- 0 or 1 PDS or Nylon
- Long acting to withstand the long healing period of tendons
List the four tendon repair suture patterns.
- Locking loop (FLAT)
- 3 loop pulley (ROUND)
- Krakow
- Double locking loop
- Double Cross Lock
- Triple circle lock
- Modified Tang
- Simple horizontal mattresses superficially
What is the recommended post-operative management for tendon repair?
- Protected bandage with no load bearing for the first few weeks
- At 3 weeks, bandage off and very restricted movement
- At 6 weeks, allow controlled exercise
True or False: By 1 year, the tendon will have 100% of its original healing strength.
False
What are the three main phases of tendon healing?
- Inflammatory (1 week)
- Proliferative (few weeks)
- Remodeling phase (many months)
What is the most likely cause of septic arthritis?
Recent surgery to a joint or pre-existing joint disease (e.g., OA)
What are the typical cytological features of joint fluid in an infected joint?
- Turbid fluid
- Increased cell counts (~ >50 x 10^9)
- Mononuclear cells ~ 1-10%
- Neutrophils ~ 90% with toxic changes, intracellular bacteria
List common bacterial isolates associated with septic arthritis in dogs.
- Staphylococcus intermedius
- Staphylococcus aureus
- Streptococci spp.
- Pasteurella multocida (CATS)
- Bacteroides spp. (CATS)
How can bacteria be isolated for culture and sensitivity testing?
- Arthrocentesis using aseptic technique
- Use blood culture medium to store synovial fluid
- Synovial tissue biopsy and culture if clinically justified
What are the medical treatments for septic arthritis?
- Arthrocentesis for fluid culture
- Systemic broad-spectrum antibiotics
- Minimum treatment duration of 28 days
- Repeat arthrocentesis to check cell count
What are the surgical treatments for septic arthritis?
- Joint irrigation
- Local antibiotic infiltration
- Arthroscopic inspection if gross contamination
- Synovial resection if needed
What is the overall prognosis for a 16-week-old puppy with an elbow joint infection?
- Improvement expected in 24-48 hours
- Infection resolved in 94% of cases
- Full recovery unlikely if pre-existing OA
What are the four aetiopathologies of canine osteoarthritis?
- Developmental disorders (secondary OA)
- Joint incongruence/instability (secondary OA)
- Trauma/Ligament injury (secondary OA)
- Idiopathic (primary OA)
List macroscopic changes seen in articular cartilage due to arthritis.
- Cartilage loss/ulceration/eburnation
- Osteophytes, enthesiophytes
- Fibrillation
- Thickened subchondral bone
What are the microscopic changes seen in articular cartilage due to arthritis?
- Extracellular matrix degrades
- Increased water content
- Chondrocytes proliferate/hypertrophy
- Vascular invasion through the tidemark
What are the mediators of arthritis?
- IL-1, IL-7, IL-18, TNF-a
- COX-2
- Reactive oxygen species
- Nitric oxide
What is the mechanism of action of NSAIDs?
Inhibit one or more steps in the metabolism of the arachidonic acid cascade and block prostaglandin synthesis.
What are potential adverse effects of NSAIDs?
- Gastric ulceration
- Renal perfusion issues
- Impaired platelet activity
Fill in the blank: The healing of a tendon with a minimal gap of less than ______ will have very little scar tissue.
[1mm]
What are the two main goals of tendon repair?
- Minimise/eliminate the gap
- Allow early loading to ensure correct collagen formation
Describe the initial phase of tendon healing.
Inflammatory phase where ends of tendons produce inflammatory products and neutrophils.
What percentage of strength is gained by 6 weeks after tendon repair?
56%
What are the components of hyaline cartilage?
- 50% collagen type II
- 35% proteoglycans
- 10% other glycoproteins
- 2-10% chondrocytes
What type of cartilage is considered the strongest?
Fibrocartilage
What is the main goal of tendon repair?
To minimise/eliminate the gap and allow early loading for correct collagen formation/alignment
This also includes restoring the normal working length of the tendon for maximum efficiency and to avoid elongation.
What are intraoperative considerations that optimise tendon healing?
Avoid direct incision over the tendon, avoid further damage to tendon ends, do not use the suture pattern to bring tendon edges together, use strong non-absorbable monofilament suture, use specialised suture patterns to resist pull out, perform end-to-end anastomosis, and debride as little as possible.
These steps help prevent scar tissue and ensure ongoing mobility.
What are the post-operative considerations to optimise tendon healing?
Avoid strain/weight bearing for the first 3 weeks, use casts/bandages/transarticular screws/ESFs to limit joint mobility, allow minimal/controlled strain from 3-4 weeks, and manage Ex-Fix’s well.
Individual responses may vary.
Which suture pattern is best for round tendons?
3 loop pulley
This pattern is specifically designed to accommodate the shape and structure of round tendons.
What differentiates vascular tendons from avascular tendons?
Vascular tendons have a surrounding paratenon, while avascular tendons have a sheath.
The paratenon provides vascular tissue and reduces friction, while the sheath allows for stretching and contains synovial fluid.
What is the function of the paratenon?
It reduces friction between the tendon and neighbouring tissues and can supply vascular buds and undifferentiated cells to the damaged tendon.
This supports the healing process.
What are the strength percentages of tendons at 6 weeks and 1 year post-repair?
56% at 6 weeks and 79% at 1 year.
This indicates the gradual increase in tendon strength over time.
What are the passive stabilisers of the shoulder joint?
Limited joint volume, adhesion/cohesion mechanisms, concavity compression, slightly negative intraarticular pressure, capsuloligamentous restraints including glenohumeral ligaments, joint capsule, labrum, and tendon origin biceps brachii.
These structures contribute to the stability of the shoulder joint.
What is the typical presentation of biceps brachii tendinopathy?
Chronic intermittent or progressive weight-bearing thoracic limb lameness, worse with exercise, often refractory to NSAIDs.
It primarily affects middle-aged to older medium to large breed dogs.
What are the potential causes of medial shoulder instability in dogs?
Congenital soft tissue laxity in small dogs and repetitive microtrauma/overuse injury in large dogs.
Signs of secondary OA are common with normal bony anatomy.
What are some delayed tendon healing factors?
Complications with healing, early weight bearing, not weight bearing soon enough, infection, insufficient suture strength, incorrect suture pattern, large gap (>3mm), poor vascular supply, prolonged inflammation.
These factors can hinder the healing process of tendons.
Fill in the blank: The sequence of collagen structures is: Collagen Fibril > _______ > Fibre Bundle > Fascicle > Tertiary bundle > Tendon.
Collagen Fibre
