Tedinopathies and Compartment Syndrome Flashcards
What is the function of a tendon?
Transmits force from muscle to achieve movement
Describe the structure of a tendon.
Parallel collagen fibrils with tenocytes
Sheathed by a paratendon sheath
Largely avascular, with nutrition supplied by the paratendon
What is a tendinopathy?
Chronic tendon injury of over use (repetitive loading)
- degeneration, disorganisation of collagen fibres
- increased cellularity as the body tries to stimulate healing
- little inflammation
What are the risk factors for developing a tendinopathy?
Age associated with activity levels Chronic disease Diabetes, RA Adverse biomechanics Repetitive exercise Recent increase in activity Quinolone antibiotics
Describe the pathology of a tendinopathy.
Not inflammation (tendinopathy not teninitis)
Deranged collagen fibres associated with a scarcity of inflammatory cells
Increased vascularity around the tendon
Failed healing resposne to micro-tears
Inflammatory meditors released (IL-1, NO, PGs) cause apoptosis, pain and provoke degeneration through release of MMPs
Name some locations of common tendinopathies.
Achilles tendinopathy Rotator cuff tendonitis Tennis elbow Golfers elbow Patella tendinopathy Hamstring tendonitis Adductor tendonitis Plantar fasciits
What are the clinical features of a tendinopathy?
Pain
Swelling
Thickening
Tenderness
How are tendinopathies diagnosed?
X-Ray - rules out other causes
Ultrasound
MRI - best seen in T1
Describe some non-operative treatments of tendinopathies.
NSAIDs Activity modification Physiotherapy GTN patches PRP injections Prolotherapy - irritant injection of dextrose Extra Corporeal Shokwave therapy - 3 weekly treatments Topaz - radiofrequency coblation Steriod injections
Describe the mechanism of action of GTN patches in tendinopathy treatment.
It is absorbed throught the skin, where it biotransforms into NO, which promotes
- extracellular collagen organisation
- collagen and protein synthesis
- vasodilations (to increase local perfusion)
Headaches are a common side effect
Describe the physiotherapy used in treatment for tendinopathies.
Eccentric loading
- contraction of the musculotendinous unit whilst it elongates
Beneficial in around 80% of patients
What are the operative treatments for tendinopathies?
Debridement
- excision of diseased tissue
- possible to remove 50% of the tendon without loss of function
Tendon transfers
Describe the prognosis of a tendinopathy.
Most will improve with activity modification
Most non-operative measures improve in symptoms in 70-80% over 1-2 years
Surgical treatments work in 80% of cases
- if non-operative methods fail
What is compartment syndrome?
An orthopaedic emergency
- can cause loss of function, limb or life
Elevated interstitial pressure within a close fascial compartment resulting in microvascular compromise
Where are the common sites for compartment syndrome to occur?
Leg
Forearm
Thigh
What are the general causes of compartment syndrome?
Increased internal pressure - bleeding - swelling - iatrogenic infiltration Increased external compression - casts/bandages - full thickness burns Combination of any of the above
Describe the pathophysiology of compartment syndrome.
Pressure within the compartment exceeds pressure within the capillaries
Muscles become ischaemic and develop oedema through increased endothelial permeability
Necrosis begins in the ischaemia muscles after 4 hours
Ischaemic nerves become neuropraxic
- this may recover if relieved early, permanent damage may result after just 4 hours
Compromise of the arterial blood supply.
Describe the effects of ischaemia over time on nerves and muscles.
1 hour
- nerve conduction normal and muscle viable
4 hours
- neuropraxia in nerves (reversible)
- reversible muscle ischaemia
8 hours
- nerve axonotmesis and irreversible change
- irreversible muscle ischaemia and necrosis
Describe the end stage of compartment syndrome.
Stiff fibrotic muscle compartments
Impaired nerve function
Clawing of limbs
Loss of function
Name some specific causes of compartment syndrome.
Internal pressure - trauma (fractures, entrapment) - muscle oedema/myositis - intracompartmental administration of fluids/drugs - re-perfusion (vascular surgery) External pressure - impaired consciousness/protective reflexes - positioning in theatre - bandaging/casts - full thickness burns
What are the clinical features of compartment syndrome?
Pain - out of proportion to that expected from the injury
Pain on passive stretching of the compartment
Pallor
Parastesia - late stage
Paralysis - late stage
- deep nerves affected first
Pulselessness - late stage
Swelling
Shiny skin
Autonomic response - sweating and tachycardia
Seen on the hand, foot, leg, thigh and forearm
How can a diagnosis of compartment syndrome be made?
Clinical signs and symptoms
Compartment pressure measurement
- normal 0-4mmHg (10mmHg with exercise)
- around 30mmHg means it is compartment syndrome
What is the treatment for compartment syndrome?
Open and constricting dressings and bandages Reassess Surgical release Later wound closure Skin grafting and plastic surgery input
Describe the process of surgical release in compartment syndrome.
Full length decompression of all compartments
Excision of any dead muscles
Wounds left open for a while
Repeat debridement until pressure is down and all dead muscles excised
Wound closure and skin grafting
