Elective Surgery Master Deck Flashcards
Options in surgical Mx of an arthritis joint?
- Arthroplasty (joint replacement)
- Excision/resection arthroplasty
- Arthroidesis
- Osteotomy
Types of arthroplasty/joint replacement?
Replacement of part of the joint (AKA hemiarthroplasty) or the whole joint (AKA total joint replacement)
Joints for which arthroplasty can be used?
Shoulder (GH joint) and elbow
Ankle, 1st MTPJ of the great toe and MCP joints of the hand and wrist
Knee and hip
Material of joint replacement?
Stainless steel, cobalt chrome, titanium alloy, polyethylene and ceramic
The component can be cemented (advantages and disadvantages)
Surfaces can consist of metal-polyethylene, ceramic-polyethylene, ceramic-eramic or metal-metal bearing couples
There is no single ideal
Why do all joint replacements eventually fail?
Loosening (wear particles produce an inflammatory response that activates osteoclasts and leads to bone resorption)
Complication of different types of joint replacements?
Can cause an inflammatory granuloma (a pseudo-tumour) that leads to muscle and bone necrosis
Polyethylene particles can cause an inflammatory response that leads to bone resorption (AKA osteolysis) - loosening
Ceramics can shatter with fatigue, due to brittleness
Describe revision surgery for a joint replacement
Removes the old components and inserts a new replacement
More difficult than the 1st time
Poorer functional outcome and more patient dissatisfaction
Why are joint replacements generally not done in younger patients?
Higher demand on the replacement increases chance of early failure and need for revision surgery
Serious complications of joint surgery?
Deep infection
Recurrent dislocation
NV injury
PE
Medical comps (renal failure, MI and chest infections, etc)
Treatment of different types of deep infection with joint replacements?
If a fulminant infection is diagnosed early (within the first 2‐3 weeks) - surgical washout, debridement and antibiotics (~6 weeks)
Deep infections present for >3 weeks - remove infected implants and all foreign material (inc. cement); patient is usually left without a joint for 6 weeks antibiotics. Once the infection is under control, a revision joint replacement is done but the joint stiffens and the overall functional outcome is poorer
Why can deep infections, in a replacement, that have been present for >3 weeks not be salvaged with washout?
Infecting bacteria adhere to the prosthetic surfaces and form a Biofilm, which prevents immune system attack
Early local complications of joint replacement?
- Infection
- Dislocation and instability
- Fracture
- Leg length discrepancy
- Nerve injury
- Bleeding and artery injury/ischaemia
- DVT
Early general complications of joint replacement?
- Hypovolaemia and shock
- Acute renal failure, MI
- ARDS
- PE
- Chest and urine infection
Late local complications of joint replacement?
- Infection (from haematogeneous spread)
- Loosening
- Fracture
- Implant breakage
- Pseudotumour formation
Describe excision or resection arthroplasty
Inv. removal of bone and cartilage of one/both sides of a joint
Types of joints on which excision/resection arthroplasty can be used?
Fairly disabling for larger joints but can be good for smaller joints, e.g:
• 1st CMCJ in hand
• Hallux valgus (Keller’s procedure)
Can be used after failure of hip/shoulder replacement
Describe arthrodesis
Surgical stiffening/fusion of a joint in a position of function; may be good for alleviating pain
Remaining hyaline cartilage of the joint and subchondral bone is removed and the joint is stabilised, resulting in bony union and fusion
Problems for which arthrodesis can be used?
- End-stage ankle arthritis
- Wrist arthritis
- Arthritis of the 1st MTPJ of the foot (hallux rigidus)
Describe an osteotomy
Surgical realignment of a bone which can be used for deformity correction OR to redistribute load across an arthritic joint
In the treatment of arthritis, the aim is to offload the diseased part of the joint and shift load to an undiseased part, e.g: from the medial compartment of the knee to the lateral compartment
Uses of osteotomy?
Early arthritis in the knee and hip
Types of soft tissue problems?
- Tendonopathies, inc. tears and ruptures
- Enthesopathies (inflammation of a tendinous origin from/insertion into bone)
- Cartilage tears
- Labrum tears
- Inflammatory bursitis
- Tenosynovitis
- Capsulitis
- Non-infective fasciitis
Causes of soft tissue problems?
Many are idiopathic
Related to degenerative processes, injuries, overuse, inflammatory conditions (RA), drugs (e.g: quinolone antibiotics, steroids) or chronic disease (renal disease)
Which treatment is substantial for most soft tissue inflammatory problems?
Conservative - rest, analgesia and NSAIDs
Major tendons may need:
• Splintage (e.g: Achilles)
• Surgical repair (e.g: quads or patellar tendon and sometimes Achilles)
• Tendon transfer (e.g: tibialis posterior, extensor pollicis longus
Treatment option for tendons and entheses?
Some tendons and entheses are amenable to injection of steroid around the tendon, e.g: rotator cuff, tennis elbow
Which tendons cannot be injected?
Substantial risk of tendon rupture and injection (Achilles and extensor mechanism of the knee)
Treatment option for refractory cases?
Refractory cases:
• Surgical debridement
• Decompression, e.g: supraspinatus tendonitis and subacromial decompression
• Synovectomy, e.g: extensor tendons of the wrist in RA or for inflammation of the tibialis posterior (to prevent rupture)
Treatment option for major tendons?
May require:
• Splintage, e.g: Achilles
• Surgical repair, e.g: quadriceps or patellar tendon and, sometimes, Achilles tendon
• Tendon transfer, e.g: tibialis posterior and extensor pollicis longus
Treatment of cartilage (meniscal) tears?
Arthroscopic removal (occasionally repair) if: • Pain fails to settle • Mechanical symptoms, e.g: locking or catching
Labral tears of the acetabulum or glenoid can be resected/repaired.
What is joint instability?
Abnormal motion of a joint (rotation or translation) resulting in subluxation or dislocation with pain and/or giving way
Causes of joint instability?
Can be a consequence of an injury OR can be related to ligamentous laxity
Can be predisposed to by anatomic variation, e.g:
• Shallow trochlea of the distal femur
• Femoral neck anteversion
• Dislocation of the patella
Can be due to an underlying disease process, e.g:
• Cervical spine instability in RA
• Knee hyperextension in polio
Conservative Mx of joint instability?
Most cases can be managed with:
• Physio (strengthen surrounding muscles and improve proprioception, e.g: ACL rupture, ankle and shoulder instability)
• Spints
• Calipers or braces may provide additional support
Surgical strategies for joint instability?
Soft tissue procedures:
• Ligament tightening/advancement, e.g: ankle instability
• Ligament reconstruction using a tendon graft, e.g: ACL
• Soft tissue reattachment, e.g: shoulder instability
Bony procedures:
• Fusion
• Osteotomy (when there is a skeletal predisposition to dislocation, e.g patellar instability)
Common sites of peripheral nerve entrapment?
Median nerve at the wrist (carpal tunnel syndrome)
Ulnar nerve at the elbow (cubital tunnel syndrome)
Treatment of nerve entrapment?
Nerve decompression surgery or disectomy, e.g: spinal nerve roots can be compressed by disc material or bony osteophytes, causing a radiculopathy
What is osteomyelitis?
Infection of bone, inc. compact and spongy bone as well as the bone marrow
Usually caused by bacteria and, occasionally, fungi
Methods of infection?
- Direct infection, e.g: penetrating trauma or surgery
- Indirectly by haematogeneous spread, e.g: from an infection or bacteraemia at a distant site, like an area of cellulitis
What does the infection depend upon?
- Bacterial load inoculated
- Virulence of the organism
- Host’s immune defenses
Which groups of people are most prone to osteomyelitis?
- Immunocompromised patients
- Chronic disease
- Elderly and young
Describe a sequestrum
Once infected, enzymes from leukocytes cause local osteolysis and pus forms which impairs local blood flow, masking the infection difficult to eradicate
A dead fragment of bone (AKA sequestrum) can form and break off; once this is present, antibiotics alone will not cure the infection
What is an involucrum?
New bone forms around the area of necrosis
Consequences of Staph. aureus’ capability to infect osteocytes?
Infection becomes difficult for the immune system to reach
Occurrence of acute osteomyelitis in the absence of recent surgery?
Usually occurs in children but immmunocompromised adults can also be affected
Problem with infection spread in children?
Metaphyses of long bone contain abundant tortuous vessels with sluggish flow, so accumulation of bacteria occurs and infection spreads towards the epiphysis
Problem with infection spread in neonates and infants?
Certain metaphyses are intra-articular, inc. the proximal femur, proximal humerus, radial head and ankle; infection can spread into the joint, causing co-existent septic arthritis
Infants also have loosely applied periosteum and an abscess can extend widely along the sub-periosteal space
Describe a Brodie’s abscess
Children can also develop a subacute osteomyelitis (more insidious onset), where the bone reacts by walling off the abscess with a thin rim of sclerotic bone (AKA Brodie’s abscess)
What is chronic osteomyelitis?
Develops from an untreated acute osteomyelitis and may be assoc. with a sequestrum and/or involucrum
Chronic OM can be suppressed with antibiotics and lies dormant before reactivating, causing localized pain, inflammation, systemic upset and possible sinus formation
Causes of chronic osteomyelitis?
In adults, tends to be in the axial skeleton (spine or pelvis) with haematogenous spread from pulmonary or urinary infections OR from infection of the intervertebral disc (discitis)
In children or adults, can be peripheral from previous open fracture or internal fixation
TB can also cause chronic OM, part. in the spine, through haematogenous spread from the primary lung infection
Causative organisms of chronic OM in various age groups?
Newborns (<4 months):
• S. aureus
• Enterobacter sp.
• Group A & B Strep.
Children (4 months - 4 years): • S. aureus • Group A Strep. • Haemophilius influenzae (reduced with vaccine) • Enterobacter sp.
Children/adolescents (4 years - adulthood): • S. aureus (80%) • Group A Strep. • H. influenzae • Enterobacter sp.
Adults:
• S. aureus
• Occasionally, Enterobacter or Streptococcus sp.
Sickle cell anaemia patients:
• S. aureus (most common)
• Salmonella sp. (fairly common and unique to sickle cell patients)
Classification of osteomyelitis?
- Superficial (affecting the outer surface of bone
- Medullary
- Localised (affecting cortex and medullary bone)
- Diffuse (segment of bone is infected, causing skeletal instability, like infected non-union)
Treatment of acute osteomyelitis?
• IV Flucloxacillin is 1st line
If there is abscess formation, this requires surgical drainage
If failure to resolve, 2nd line antibiotics may be used OR surgery may be performed to gain samples for culture, remove infected bone and washout the infected area
Treatment of chronic osteomyelitis?
Cannot be cured/eradicated by antibiotics alone
Active infection can be suppressed with antibiotics but this may prove unsuccessful
Debridement is recommended and, if this results in instability, the bone must be stabilized by internal or external fixation; IV antibiotics are continued for several weeks after surgery
Predisposing factors to osteomyelitis of the spine?
- Poorly controlled diabetes
- PWIDs
- Other immunecompromised patients
Lumbar spine is the commonest location
Presentation of OM of the spine?
Insidious onset of back pain, which is CONSTANT AND UNREMITTING
Paraspinal muscle spasm and spinal tenderness
May have fever and/or systemic upset
Neuralgic deficit (severe cases)
Complications of spinal OM?
Pus may extrude forming a paravertebral or epidural abscess
As the vertebral end plates weaken, vertebrae may collapse and this leads to kyphosis or vertebra plana flat vertebra) and disc space may reduce
Endocarditis
Ix for spinal OM?
MRI delineates extent of the infection and any abscess formation
Blood cultures may indicate causative organism (usually Staph. aureus, inc. MRSA but atypical infections can occur in the immunocompromised)
Consider an ECHO for endocarditis
Treatment of spinal OM?
High dose IV antibiotics, following CT-guided biopsy to obtain tissue culture (may be required for several months)
Indications for surgical debridement, stabilisation and fusion of adjacent vertebrae:
• Inability to obtain cultures by needle biopsy
• No response to antibiotic therapy
• Progressive vertebral collapse
• Progressive neurological deficit
Methods of infection of orthopaedic surgical implants?
Bacteria can enter the operative site at the time of surgery (usually from patient’s skin, bacteria buried deep in the hair follicles or from shed skin cells of staff)
Can enter the wound post-operatively
Bacteria infect a prosthetic joint at a later stage by haematogenous spread
Complications of prosthetic joint infection?
Chronic infection with pain, poor function, recurrent sepsis, chronic discharging sinus formation and implant loosening
Complications of deep infection with fracture fixation or stabilisation?
Risk of chronic OM and non-union of the fracture
Common organisms causing early prosthetic infection?
- Staph. aureus
* Gram -ve bacteria, inc. coliforms
Organisms causing an indolent, “low-grade” infection that is diagnosed late?
• Staph. epidermidis (AKA coagulase -ve Staph.)
Organisms assoc. with late onset haematogeneous infection?
- Staph. aureus
- β-haemolytic Strep.
- Enterobacter
