MSK Growth, injury + repair - tendons/ligaments

Question 1

Describe the structure of tendons and its coverings/layers

Answer 1

Has longitudinal arrangement of cells (mostly tenocytes) and fibres (collagen type 1 – triple helix)
Contains fascicles of long, narrow + spiralling collagen bundles
- Collagen bundles covered by endotendon
- Fascicles covered by paratendon
- Tendon covered by epitendon

Question 2

Describe the function and characteristics of tendons

Answer 2

Attach muscle to bone.
Flexible and very strong in tension.
Movement is life; immobility reduces water content & glycosaminoglycan concentration and strength.

Question 3

What are the different types of tendon injury?

Answer 3

Degeneration
Inflammation 
Enthesiopathy 
Traction apophysitis 
Avulsion +/- bone fragment 
Tear – intrasubstance (rupture) or musculotendinous junction.
Laceration/incision

Question 4

Give an example of a tendon degeneration injury and explain it

Answer 4

e.g. Achilles tendon:
Intrasubstance mucoid degeneration. May be swollen, painful, tender; may be asymptomatic. Possibly a precursor to rupture.

Question 5

Give an example of a tendon inflammation injury and explain it

Answer 5

e.g. de Quervain’s stenosing tenovaginitis:
Inflammation of tendon sheath containing EPB + APL radial aspect of wrist. Swollen, tender, hot, red.
Positive Finklestein’s test (where examiner grasps the thumb and ulnar deviates the hand sharply, if sharp pain occurs along the distal radius – de Quervain’s is likely)

Question 6

Explain enthesiopathy

Answer 6

Inflammation at insertion to bone:

• Muscle/tendon – usually at muscle origin rather than tendon insertion – e.g. lateral humeral epicondylitis (tension elbow) which is common extensor origin
• Ligament – plantar fasciitis

Question 7

Explain an example of traction apophysitis

Answer 7

e.g. Osgood Schlatter’s disease:
- Inflammation at Insertion of patellar tendon into anterior tibial tuberosity
Occurs with: Adolescent active boys, Recurrent load

Question 8

Explain tendon avulsion +/- bone fragment injury

Answer 8

• Injury to bone in location where tendon/ligament attaches to bone, tendon/ligament pulls bone away
• Failure at insertion
• failure w/ Load exceeding strength while muscle contracting

Question 9

Give an example of tendon avulsion +/- bone fragment injury

Answer 9

Mallet finger: injury at insertion of extensor tendon into dorsum at base of distal phalanx; causes forced flexion of finger.

Question 10

Give an example of intrasubstance tear (rupture)

Answer 10

e.g. Achilles tendon: load exceeding strength failure.

Question 11

What is the mechanism/causes of an intrasubstance tear?

Answer 11

Pushing off with WB forefoot whilst extending knee joint (53%) e.g. sprint starts or jumping movements
Unexpected dorsiflexion of ankle (17%) e.g. slipping into hole
Violent dorsiflexion of plantar flexed foot (10%) e.g. fall from height

Question 12

Give an example of a musculotendinous junction tear

Answer 12

e.g. medial head of gastrocnemius at musculotendinous junction with Achilles tendon: “plantaris syndrome” (misnamed), often partial.

Question 13

Describe lacerations/incisions injuries of tendons

Answer 13

Especially common w finger flexors (FDS + FDP) – common, M>F, young adults, repair surgically + early, “technically challenging”.

Question 14

Describe the treatment of tendons in avulsion injuries

Answer 14

Conservative: limited application, retraction tendon.

Operative – reattachment tendon, through bone, fixation bone fragment.

Question 15

Describe treatment of tendon ruptures

Answer 15

Conservative: 
-	Where ends can be opposed
-	Mobilise (partial rupture)
-	Splint/cast 
-	Where healing will occur
-	Not intraarticular
Operative – Where high risk re-rupture, high activity, ends cannot be opposed

Question 16

What are ligaments and their function?

Answer 16

Dense bands of collagenous tissue. Span joint and are anchored to bone at either end. Provide joint stability through a range of motion + different portions of ligament are tensioned at different joint positions.

Question 17

Describe the structural features of ligaments

Answer 17

Collagen fibres (type 1). 
Communicating fibroblasts
Sensory fibres: proprioception, stretch, sensory. 
Surface vessels 
Crimping (compress) to allow stretch

Question 18

What causes ligament rupture?

Answer 18

Forces exceed strength ligament: Expected or Unexpected (position/muscle) or Rate load

Question 19

Describe the possible results of ligament rupture

Answer 19

Can be complete injury or incomplete
Stability of joint can be compromised depending on which ligaments have been ruptured.
Proprioception loss possible

Question 20

What are the healing phases of ligament ruptures?

Answer 20

Haemorrhage
Proliferation phase
Remodelling

Question 21

Describe the haemorrhage phase of ligament rupture repair

Answer 21

Haemorrhage – blood clotting, resorption, replaced with heavy cellular infiltrate; hypertrophic vascular response.

Question 22

Describe the proliferative phase of ligament rupture repair

Answer 22

Proliferation phase – production of scar tissue; disorganised collagenous connective tissue

Question 23

Describe the remodelling phase of ligament rupture repair

Answer 23

Remodelling – matrix become more ligament like; major differences in composition, architecture and function persist.

Question 24

Outline the treatment of a ligament rupture

Answer 24

Conservative: if partial, no instability, poor candidate for surgery
Operative: if instability, expectation (Sportsmen), compulsory (multiple).