Dan, an orthopaedic consultant, and avid wrestler presented to the ED department with right sided shoulder pain and deformity post falling onto his right shoulder during a wrestling match. He suspects he has an AC joint disruption and as you are a junior doctor in ED he starts questioning your knowledge. 




"What ligaments stabilise AC joint?"

As you have read junior bones you keenly answer, "the ACJ stabalised by the..:
1.     Acromioclavicular ligament: provides horizontal stability, has 4 components (superior, inferior, anterior and posterior component)
2.     Coricoclavicular ligaments: provides vertical stability, this is comprised of:

1. Trapezoid ligament: located 3 cm from the lateral end of the clavicle
   
2. Conoid ligament: located 4.5cm from the lateral end of the clavicle
   

Dr Dan's Xray is below, please interpret..

Remember to go back to basic principles: identify patient, date, view and see if there are previous Xrays and additional views. Also ensure you have imaging of the contralateral ACJ for comparison.

The above AP Xray demonstrates widening of the right coricoclavicular distance, the right clavicle is superiorly displaced 100% (normally compared to other side), suggestive of a type 3 acromioclavicular distance, however, additional views would be required to confirm this.

Note: to visualize the AC ligament you can ask for imaging at 1/3 penetration

What other imaging (views) would you order?

• Axillary lateral: required to diagnose type 4
  
• Zanca view: tilt the Xray 10-15deg towards cephalic direction and using only 50% of the standard AP penetration strength

Describe Rockwell Classification of AC Joint Injuries:

What are the management options for Dr Dan's Grade 3 ACJ injury?
Remember: conservative vs operative
And the 4 basic principles: reduce, fix, wait, rehabilitate

Conservative Management
Indication: Types 1, 2, 3 (not in labourers, elite athletes)
ICE, rest and sling for 3 weeks
Rehabilitation: early ROM, regain functional movement by 6 weeks and return to normal activity by 12 weeks
Complications : ACJ arthritis, chronic subluxation and instability

vs

Operative Management: ORIF or ligament reconstruction
Indication: Types 3 (labourers, athletes), 4, 5, 6
Contraindications: poor compliance with post operative rehabilitation, skin problems over surgical site
Rehabilitation: sling, with no abduction for 6 weeks, no shoulder ROM for 6 weeks, return to normal activity at 6 months

ORIF with hook plate:

• Approach: exposure of middle and distal clavicle, hook plate positioned over superior distal clavicle and ‘hooked’ under the acromian.
  
• Pros and cons: rigid fixation, often requires removal of plate, high rate of acromial wea.
  

ORIF with CC suture fixation:

• Approach: proximal aspect of anterolateral approach to the shoulder
  
• Technique: suture placed around/through clavicle and around the base of the coracoid (+/- suture anchors for coracoid fixation)
  
• Pros and cons: requires careful suture passage inferior to coracoid. Minimal risk of hardware failure or migration, suture not as strong as screw fixation.
  

ORIF with screw fixation:

• Approach: proximal aspect of the anteriorlateral approach to the shoulder
  
• Technique: screw from distal clavicle into coracoid
  
• Pros and cons: rigid fixation, danger of screw damaging critical structure below coracoid, complicated by hardware irritation or failure.
  

CC Ligament reconstruction: with free tendon graft OR Modified Weaver-Dunn (transfer of coracoacromial ligament to the distal clavicle to recreate CC ligament)

• Approach: proximal aspect of the anteriorlateral approach to the shoulder +/-  harvest site (hamstring/Palmaris tendon)
  
• Pros and cons: coracoacromial ligament not as strong as normal CC ligament vs graft which recreates strength of native CC ligament but standard risk of graft use.

 

Above is Dr Dan's post operative Xray. He was managed with corico-clavicular suture fixation. 


REFERENCES:

Abbasi, D. Badylak, J. 2015. Acromio-Clavicular Injuries (AC Seperation). Orthobullets. Accessed: 15/7/15

Caribbean Sports Orthopaedic Clinic, 2010. ACJ Reconstruction. Available from: https://www.c-soc.com/surgical/treatments/shoulder/acj-reconstruction/ Accessed: 20/7/15

Sinnerton, R. ACJ (Hook Plate, Surgilig) Available from: http://www.lu-lu.co.uk/operations/acromio-clavicular-joint/ Accessed: 17/7/15.

The Physio Lounge, 2014. Skiing Injuries. Available at http://www.physiolounge.co.uk/skiing-injuries/. Accessed: 14/7/15

You are on night ward call and a nurse calls you to review a post operative patient for worsening leg pain. James, a 25 year old male, is day 1 post right intramedullary tibial nail. You have been called multiple times about James for pain relief. He has low pain tolerance and is suspected to use regular recreational drugs.

What questions would you ask the nurse?

1. Neurovascular observations - including capillary refill
2. Amount of analgesia used
3. Background

also consider:

• known bleeding disorder
• does he have a cast in situ

REMEMBER: compartment syndrome can occur wherever skeletal muscle is surrounded by fascia, including leg (similar to this case), forearm, hand, foot, thigh, buttocks, shoulder, etc
     
Pathophysiology of compartment syndrome

1. trauma/ soft tissue destruction
   
2. bleeding and oedema
3. increased interstitial pressure
4. vascular occlusion
5. myoneural compromise

Majority of cases are secondary to fractures

What are the 6 P's of Compartment Syndrome and what are late and early signs? Hint: think of the pathophysiology above (Stracciolini, Hammerberg 2015)

1. Pain on passive stress - early sign - most sensitive
2. Palpable swelling - woodlike
3. Paraesthesia -reduced sensation secondary to ischaemic nerve dysfunction
   
4. Poikilothermia 
5. Pallor - unusual finding
   
6. Peripheral pulses absent - late finding
   

Realistically the patient will complain of pain out of proportion, described as a deep ache or burning pain, deep ache or burning pain and potentially paraesthesia and muscle weakness (onset is usually 30minutes to 2 hours of acute compartment syndrome).

Interpreting Clinical Findings:

• Capillary refill becomes compromised if compartment pressure reaches 25-30mmHg of mean arterial pressure
• Pain develops with compartment pressure of 20-30mmHg
• Ischaemia occurs if compartment pressure reaches diastolic pressure

What are the 4 compartments of the leg and define what structures are within them?
1. Anterior Compartment:

• Function: dorsifllexion of foot and ankle
• Muscles within compartment: tibialis anterior, extensor hallucis longus, extensor digitorum longus, peroneus tertius

2. Lateral Compartment

• Function: plantarflexion and eversion of foot
• Muscles within compartment: peroneus (fibularis) longus, peroneus brevis
• Nerve: isolated lateral compartment syndrome would affect superficial peroneal nerve

3. Deep Posterior Compartment

• Function: plantarflexion and inversion of foot
• Muscles: tibialis posterior, felxor digitorum longus, flexor hallucis longus

4. Superfical Posterior Compartment

• Function: plantarflexion of foot and ankle
• Muscles: gastrocnemius, soleus, plantaris

REMEMBER: you will never get told off for removing a cast if you suspect compartment syndrome
How to measure compartment pressures?

How do I measure compartments?
3 methods are used frequently:
1. A handheld manometer (eg, Stryker device)
2. A simple needle manometer system, and
3. The wick or slit catheter technique
Both manometer methods involve injecting a small quantity of saline into a closed compartment and measuring the resistance from tissue pressure

The normal pressure of a tissue compartment falls between 0 and 8 mmHg (Klenerman L, 2007)

Procedure:
Should aim to measure pressures within 5cm of fracture site.

• Anterior Compartment: enter perpendicular to skin 1cm lateral to anterior border of tibia
• Deep Posterior Compartment: enter perpendicular to skin, just posterior to the medial border of tibia
• Superficial Posterior Compartment: enter middle of calf
• Lateral Compartment: enter just anterior to posterior border of fibula

Treatment:
Non-operative:
1. Bi-Valve James' cast
2. Observe: if not consistent with compartment syndrome
3. Hyperbaric oxygen therapy: increases oxygen diffusion gradient

Operative: Emergent fasciotomy of all four compartments
Indications:

• Compartment pressures of 30-45mmHg
• Clinical presentation with compartment syndrome
• Compartment pressures within 30mmHg of diastolic BP

Procedure
1. Dual (2 incisions) medial and lateral incision: 2 x 15 cm incisions

2. Single lateral incision from head of fibula to ankle along line of fibula

REFERENCES
Karadsheh, M. 2015 Leg Compartment Syndrome. Orthobullets. Available from: http://www.orthobullets.com/trauma/1001/leg-compartment-syndrome. Accessed 10/7/15.

Klenerman L. The evolution of the compartment syndrome since 1948 as recorded in the JBJS (B). J Bone Joint Surg Br 2007; 89:1280.

Stracciolini, A., Hammerberg, E. 2014. Up To Date. Acute Compartment Syndrome available from: http://www.uptodate.com/contents/acute-compartment-syndrome-of-the-extremities#H8 Accessed 1/7/15