- Acute infection of bone usually initiated by haematogenous dissemination of bacteria
- Can also be caused by granulomatous, viral & parasitic processes
- Osteomyelitis coined by Nelaton in 1844
- Lexer in 1894 injected measured doses of S aureus into animal veins & after traumatization of bone, osteomyelitis developed
- Hobo in 1921 described the metaphyseal blood supply & its relevance to osteomyelitis
- Trueta in 1928 saw mortality of 20% before antibiotic therapy but dropped to 3.5% with sulphonamides & then almost zero in last 40 years
- Hoyt, Davis & Van Buren in 1941 found nonop treatment successful & so raised the issue of operative neccessity
Continue reading Acute Osteomyelitis
- Mid-substance calcification of the rotator cuff as part of a metaplasia secondary to hypoxia
- Different condition to dystrophic calcification of a degenerate cuff which occurs at the cuff insertion
- Not due to impingement
- Two theories
- Degenerate calcification theory
- Dystrophic calcification of degenerate cuff
- Necrotic fibrillated fibres act as nucleus for calcification
- Evidence against this theory as dystrophic calcification has different histology
- Degenerate cuff with true calcific tendonitis rare
- Reactive Hypoxic Calcification Theory
- Codman proposed cuff hypoxia as the causative factor
- Viable cells undergo metaplasia to fibrocartilaginous cells
- Fibrocartilage cells accumulate intracellular calcification
Classification of Calcific Cuff Tendinopathy
- No pain or chronic pain
- “Chalk” appearance
- Well-defined calcification on XR
- Acute pain
- Fluffy appearance on XR
- Macrophage resorption
||Area heals to scar
- Usually acute pain due to calcification
- Acute pain in Resorption phase on background of Absent to mild chronic pain of the Formative Stage
- No impingement
- Cuff Tendinopathy
- Brachial Neuritis
- Septic Shoulder
- Biceps Tendinopathy
- Gout/ CPPD
- Pre-Calcific Stage
- Fibrocartilaginous metaplasia of avascular cuff tenocytes
- Occurs due to hypoxia
- Calcific Stage
- Formative part of Calcific Stage
- Calcification accumulates in matrix vesicles
- Calcification deposited
- Into extra-cellular matrix of
- Amorphous GAG rich debris
- Fragmented collagen fibres around viable chondrocytes
- Calcification is crystalline & noncrystalline
- Crystals may be in the form of
- Resorptive Part of Calcific Stage
- Calcification as a hyperaemic area = “strawberry lesion”
- Calcium Granuloma forms
- AKA ” Psammoma”
- Increased intratendinous pressure
- Post-Calcific Stage
- Granulation tissue fills space left by Calcification
- Forms scar
- Calcification typically Supraspinatus mid-cuff
- Two appearances
- Painful Resorptive (Type 1)
- Poorly defined margin
- Can rupture into bursa
- Chronic Formative (Type 2)
- Discrete, homogenous deposit
- Well defined margin
- Uniform density
- Degenerative changes extremely rare with true calcific tendonitis
- Different appearance to dystrophic calcification secondary to a cuff tendinopathy
- more sensitive than XR
- ~ 100%
- Cortisone not recommended
- Distinguish Formative vs Resorptive
- Formative Management
- Typically Non-Operative
- Physiotherapy to maintain ROM
- ? USS
- HCLA if concomitant impingement
- Don’t needle or lavage
- If above fails surgery may be needed
- Deltoid split
- Split fibres longitudinally
- Scoop out Calcification
- May need II
- Repair cuff
- Acromioplasty if cuff tight
Rupture of Long Head Biceps
- 50% of biceps ruptures
- Two groups
- Young people with sudden unexpected lifting
- Older patients (middle age or elderly) with associated impingement and little or no trauma
- Isolated ruptures of biceps tendon only seen in 25% of cases
- Rest had involvement of supraspinatus
Function of Biceps
- Flexion of supinated forearm
- Supination of the flexed forearm
- Flexion of shoulder
- Prevention of anterior displacement of G-H joint
- Deceleration of the rapidly extending elbow (as in throwing)
- Sudden pain with lifting
- Characteristic bulging arm contour “Popeye Muscle”
- Soon after pain settles
- 20% loss of flexion power
- Normal elbow flexion power
- 10% loss of supination power
- Non operative
- Indicated in most patients
- Young patient with recent rupture that won’t accept deformity or mild loss of power
- Particularly supination power
- Older patient as part of treatment for impingement
- Deltopectoral approach
- Expose intertubercular groove
- Divide transverse humeral ligament
- Remove infraglenoid component of the tendon
- Keyhole in the floor of groove
- 1cm upper round portion
- 0.5cm distal portion
- Roll or suture the biceps tendon
- Insert into hole and close periosteum over it
- Restrict elbow extension for 4/52 postoperative
Dislocation of Biceps Tendon
- Medial dislocation of Biceps tendon from the groove
- Attrition rupture of transverse humeral ligament
- ± Associated rotator cuff tear
- Acute traumatic rupture of transverse humeral ligament
Classification of Biceps Tendon Subluxation / Dislocation
||Subluxation at the groove
||Malunion / Nonunion of Lesser Tuberosity
- Pain in anterior shoulder
- Dislocation / Subluxation of Biceps Tendon with abduction & external rotation
- Snapping sensation
- Reflex dropping of arm with subsequent relocation of tendon
- tenderness in groove
- Attempt to dislocate tendon
- Pain and pop with Yerguson’s test in adduction
- Recurrent anterior GHJ dislocation (same position of abduction with ER)
Biceps Tendonitis/ Tenosynovitis
- Part of impingement syndrome with
- Rotator cuff tendonitis
- Subacromial bursitis
- Pain in anterior shoulder
- Worse with overhead motion
- Pain at night especially lying on side
- Tendon tender in groove
- Anterior pain on ER
- Speed’s Test
- Shoulder flexed
- Elbow extended & forearm supinated
- Pain on resisted elevation
- Yergason’s Test
- Elbow 90°
- Pain with resisted supination
- Changes of impingement
- Bicipital groove shallow with medial and lateral osteophytes
- Narrowed attenuated tendon or vacuolation
- Elevation from floor by inflamed synovium
- Poor or no filling of sheath
- Inflammation or attenuated tendon
- Narrowed attenuated tendon
- Increased signal intensity on T2
- Elevation of biceps from groove or origin by inflamed synovium
- Usually non-op
- As for impingement
- If fails then Tenodesis of tendon
Anatomy and Pathology
- Physis Closure
- In adolescence, the distal tibial physis starts to close first at the anteromedial aspect of the medial malleolus, and the closure then extends posteriorly and laterally.
- The last part of the physis to close is the anterolateral quadrant of the physis. This quadrant has the anterior tibiofibular ligament attached to it. If the foot externally rotates, this part of the epiphysis is pulled off, resulting in a juvenile Tillaux fracture.
- Tillaux Fracture
- The juvenile Tillaux fracture is essentially a Salter-Harris III fracture of the distal tibial physis
- Triplane Fracture
- If the fracture line extends across the metaphysis, this creates a triplane fracture.
- A triplane fracture essentially has the appearance of a SH III fracture on the AP and a SH II fracture on the lateral
- External Rotation injury
- AITFL avulses anterolateral tibial epiphysis, corresponding to distal tibial physis which remains open
- Can be Isolated or Associated with ipsilateral shaft fractures
- Fibula usually prevents marked displacement
- Mortise view essential to aid diagnosis
- CT Scan
- very helpful
- tillaux vs triplane
- AKPOP: knee flexed 30° & foot IR
- Confirm reduction with CT scan
- Watch carefully
- Attempt closed reduction
- IR of foot with direct pressure over anterolateral tibia or dorsiflex & IR pronated foot
- stabilize with percutaneous pins or cannulated (4.0mm) screw ± washer
- can cross physis, growth is not a concern
- Confirm with CT scan
- If Closed Reducations fails
- first attempt to guide into position with 2 percutaneous smooth pins
- ORIF if fails.
- Anterolateral approach, with cannulated or cancellous screws.
- Must identify & protect SPN.
- BK NWB cast x 3wks, then WB x 3 wks
- sandbag under spine & medial border of scapula
- beachchair to 30°
- Mayfield head rest
- Prep & drape arm free
- Coracoid process
- Deltopectoral groove
1. Anterior incision
- Start: just above coracoid process
- 10-15 cm along line of deltopectoral groove
2. Axillary incision
- abduct shoulder 90° & ER
- start: midpoint of anterior axillary skin fold
- vertical incision 8-10 cm
- end: towards axilla
- deltoid: axillary nerve
- pectoralis major: medial & lateral pectoral nerves
- identify deltopectoral groove
- cephalic vein laterally
- deltoid laterally
- pect major medially
- conjoint tendon: short head of biceps (MC nerve), coracobracialis (MC nerve) taken medially
- Axillary artery lie behind pect minor
- Keep arm adducted during procedure to protect artery
- Musculocutaneous nerve
- On medial side of coracobracilis
- Deltopectoral fascia
- Subscapularis tendon
- ER arm to stretch subscap & makes it easier to define
- Also ? gap between subscap & axillary nerve (at its lower border, quadrangular space)
- Ligate triad of small vessels*2 veins 1 artery) at inferior border
- Superior border of SubS is indistinct & blends with supraspinatus
- Tag tendon
- Detach subscap off lesser tuberosity insertion
- Musculocutaneous nerve
- Enters CB 5-8 cm distal to coracoid process
- From medial side
- Cephalic vein
- For Waist & distal scaphoid fractures
- Retrograde fixation
- Use standard Herbert or Accutrax
- GA, ABx, Tourniquet, Supine, Arm table, Prep, Drape (including crest)
- Prep & drape iliac crest
- Radial styloid
- FCR tendon
- Scaphiod tubercle
- Distal wrist crease
- Curvilinear incision centred over FCR
- Longitudinal incision for 3cm prox to wrist along line of FCR then at wrist crease curve radially toward ST joint
- More proximal than you think
- Blunt dissection to protect palmar branch of median N
- Open FCR sheath & retract ulnarly
- Carefully dissect distally
- Identifying & Ligating the superficial palmar branch of the radial artery
- Extension & ulnar deviation of wrist
- Incise through the bed of FCR
- volar radioscaphoid joint capsule
- radio-scapho-capitate ligaments
- exposures volar surface of scaphoid
- insert self retaining retractor
- Identify the fracture site
- Extend the incision sharply slightly into the origin of thenar muscles & over the scaphoid tubercle
- Peel the ligaments off radially & ulnar
- But preserve radially group of vessels entering scaphoid
- Identify # & assess. ? needs bone graft if comminuted or tending into flexion.
- Mobilise the scapho – trapezium joint
- Allowing the distal pole to be elevated (with elevator) enough to allow proper placement of guide wire
- Pulling on index & long finger will aid in exposure
- Fracture assessment & reduction
- ? need for bone graft
- infuse area with Marcaine & adrenalin
- harvest from iliac crest
- Reduce #, hold with Herbert-Whipple screw clamp, pass guidewire, II in 2 planes, measure, drill, tap, screw. (or use K wires for fixation)
- Release tourniquet, haemostasis, close, POP
- There are five simple patterns and five associated fracture typesSimple fracture types:
- Posterior wall
- Commonest type (25-33%). Very commonly associated with a hip dislocation (eg 86/100 in Moed’s study)
- Posterior column
- Anterior wall
- Anterior column
- Transverse fractures
- Transtectal – transverse fracture line crosses superior acetabular articular surface
- Juxtatectal – fracture line crosses at the junction of the superior acetabular articular surface and the superior cotyloid fossa
- Infratectal – fracture line crosses through the cotyloid fossa
Associated fracture types:
- Associated posterior column and posterior wall
- Associated transverse and posterior wall
- T shaped
- Associated anterior column and posterior hemitransverse – subtle distinction from T shaped fractures. In the T shaped fracture the fracture line is horizontal with a stem; in the anterior column/posterior hemitransverse the anterior component is higher up and typically more displaced than the posterior component
- Both column fractures – the essential component of this fracture is that all elements of the articular cartilage are divided from the ilium. This sets this type of fracture apart from the transverse, T shaped, associated anterior column and posterior hemitransverse and associated transverse and posterior wall fractures
In Matta’s series 21% were simple fracture types and 79% associated fracture types (this was a tertiary referral load).
Commonest fracture type was both column fracture (35%).
- Young adults, car crashes
- ~50% have another serious injury
The acetabulum can be divided into two columns, anterior and posterior
- Anterior column
- Anterior border of the iliac wing
- Entire pelvic brim
- Anterior wall of the acetabulum
- Superior pubic ramus
- Posterior column
- Greater sciatic notch
- Lesser sciatic notch
- Posterior wall of the acetabulum
- Majority of the quadrilateral surface
- Ischial tuberosity
Judet and Letournel consider the acetabulum to be located in the cavity of an arch formed by two columns of bone, one anterior and the other posterior.
The posterior column is also called the ilioischial column and the anterior column iliopubic
Biomechanics of normal hip
- The normal hip is not completely congruent.
- There is conflicting data on the patterns of loading in the normal hip.
- ? weight in born on the periphery of the acetabulum (Charnley and Hammond)
- ? loading occurs predominantly in the roof of the acetabulum.
Pathoanatomy and classification
- The fracture pattern depends on the orientation of the femoral head at the moment of impact.
- If it is internally rotated, a posterior wall fracture will be produced.
- If it is adducted, the dome of the acetabulum will be disrupted.
- Many surgeons use Letournel’s modification of Judet’s 1964 classification.
- It is designed to guide the operative approach rather than provide a prognosis.
- There are five simple patterns and five associated fracture types
- AP, obturator oblique, iliac oblique (Judet views)
- there are certain lines that if disrupted indicate a fracture of that region:
- Iliopectineal line
- a landmark of the anterior column
- Ilioischial line
- represents the posterior portion of the quadrilateral surface and therefore a radiographic landmark of the posterior column
- The teardrop
- which consists of a lateral and medial limb
- Lateral limb: inferior aspect of the anterior wall of the acetabulum
- Medial limb: obturator canal and anteroinferior portion of the quadrilateral surface
- The teardrop and ilioischial line are always superimposed in a normal acetabulum.
- Roof of the acetabulum
- superior aspect of the acetabulum
- Obturator oblique view
- taken with the pelvis internally rotated 45 degrees (by lying on a wedge shaped cushion)
- This view throws the anterior column into prominence
- best way of making out fractures of the posterior wall of the acetabulum.
- Iliac oblique view
- taken with the pelvis externally rotated 45 degrees
- shows the iliac wing and posterior column, and the anterior rim of the acetabulum best.
- provides additional information, eg on bony fragments within the joint space, cartilage fragments which can be inferred from joint space widening, and 3D reconstruction which can allow removal of the femoral head from the picture to simplify things.
- Nondisplaced fractures
- Acceptable displacement
- Large part of roof of acetabulum is intact and femoral head articulates with this surface
- eg. low anterior column or transverse type fractures (infratectal).
- assessed by looking at the CT films 10mm below the apex of the roof
- if there are no displaced fracture lines (>2mm) here there will be an arc of at least 90 degrees of normal roof
- provided the hip is congruent nonoperative treatment can be considered.
- Roof arcs can also be measured on plain films.
- Secondary congruence after moderate displacement of both column fracture
- often contingent on the presence of an intact acetabular labrum
- treatment skeletal traction
- prevents further shortening.
- traction must not distract the femoral head from the acetabulum
- traction cannot be used to reduce a displaced acetabular fracture
- 20 to 30 pounds via a supracondylar pin in nonoperatively treated fractures.
- Surgical contraindications
- eg infection or gross osteoporosis
- 45 days of bed rest
- passive ROM and massage
- then another 45 days of touch weightbearing.
- Displacement of more than 2mm through weight bearing dome.
- Special situations:
- Posterior wall fragments
- Loading is altered by as little as 33% loss of posterior wall
- Hip instability occurs with loss of 20-65% of width of posterior wall
- If in doubt about need to fix can assess with EUA and fluoroscopy
- Osteochondral fragments
- If the fragments are preventing a congruent reduction of the hip joint they should be removed
- Timing of surgery
- delayed for at least 2-3 days
- to allow bleeding to settle,
- dislocation of the femoral head which mandates immediate reduction.
- If performed more than 10 days post
- fracture callus makes the operation more difficult.
- No one surgical incision is ideal for all fractures of the acetabulum.
- All three of the main approaches provide some access to both the columns.
Surgical approaches for Acetabular Fractures
||best access to the posterior column
||anterior column and the inner aspect of the innominate bone.
|extended iliofemoral approach
||best simultaneous approach to both columns but:
- The approach to the anterior column isn’t as good as the ilio-inguinal approach
- It has the longest postoperative recovery
- It has the highest incidence of ectopic bone formation
- It has the highest blood loss
- it is preferable to choose the Kocher-Langenbeck or ilio-inguinal approach if possible.
- Surgery should be done through one approach if possible
- posterior wall and column fractures
- This has several advantages:
- Femoral head lies in a reduced position
- The tendency for the femoral head to translate medially is eliminated
- Controlled traction is available by means of a fracture table while allowing flexion of the knee to relax the sciatic nerve
- starts lateral to the PSIS, proceeds to the greater trochanter and then continues along the axis of the femur to almost the midpoint of the thigh.
- Gluteal fascia is split in line with the fibres of gluteus maximus
- Fascia lata is split in line with the axis of the femur
- The gluteus maximus is posteriorly reflected
- The sciatic nerve is identified on the posterior surface of quadratus femoris and followed proximally until it disappears under piriformis
- The tendons of piriformis and obturator internus are transected at their trochanteric insertion and retracted posteriorly which exposes the greater and lesser sciatic notch
- Subperiosteal elevation exposes the inferior aspect of the iliac wing.
- The capsule can be opened along its rim and the femoral head distracted to expose the interior of the joint.
- Virenque suggested a modification whereby the sciatic spine is cut at its base; this provides an excellent view of the quadrilateral plate.
- anterior column fractures
- supine, with hip flexed 20 to 30 degrees to relax the psoas tendon. Insert IDC.
- from 2 fingerbreadths above the symphysis pubis, to ASIS, then two thirds along the iliac crest.
- The periosteum is incised along the line of the iliac crest
- The iliacus is reflected from the interior aspect of the iliac wing
- The aponeurosis of the external oblique (which forms the roof of the inguinal canal) is incised and the spermatic cord isolated and protected; beware of ilioinguinal and iliohypogastric nn
- An incision is then made along the floor of the inguinal canal and then the inguinal ligament from the pubic tubercle to the ASIS.
- The iliopectineal fascia, which covers the internal aspect of the iliacus and plasters down the femoral nerve is released
- Access to the internal aspect of the innominate is obtained via three windows, medial to the femoral artery and vein, between the neurovascular structures and iliopsoas and lateral to psoas. The vertical structures are defined, isolated with vessel loops and moved from side to side to gain access to the bone.
- The interior of the joint cannot be seen after the fracture has been reduced.
Extended iliofemoral approach
- both column fractures
- Provides access to the entire acetabulum, external iliac wing and the entire posterior column.
- lateral, with knee flexed to relax the sciatic nerve or
- supine with a sandbag under the ipsilateral buttock.
- starts at the PSIS,
- follows the iliac crest to the ASIS,
- then turns laterally to parallel the femur on the anterolateral aspect of the thigh.
- The periosteum is reflected from the iliac crest and the gluteal muscles released from the iliac wing.
- Beware of the superior gluteal vessels, which nourish the gluteal flap thus created.
- The anastomotic supply to the abductors is the ascending branch of the lateral femoral circumflex artery, and this is necessarily divided.
- The tendons of gluteus medius, gluteus minimus, piriformis and obturator internus are transected and reflected posteriorly to expose the ischial spine and sciatic notches.
- An incision along the acetabular rim through the joint capsule provides access to the interior of the joint if the femoral head is distracted
- The reflected tendon of rectus femoris is usually divided
- Sartorius and rectus femoris can be released from the ASIS to provide access to the internal aspect of the iliac wing, and this also allows access to the upper portion of the anterior column
- lateral, with knee flexed
- From the PSIS to the GT, from the ASIS to the GT, and then from the GT down the femoral shaft.
- Generous flaps are raised down to the fascia
- The gluteus maximus and tensor fascia lata is exposed and incised in a Y type incision.
- This exposes the gluteus medius which is elevated via a trochanteric osteotomy
- The entire side wall of the pelvis is thus exposed from the anterior to the posterior iliac spine
Summary Choice of Incision
- Anterior wall
- Anterior column
- Anterior column-posterior hemitransverse
- Posterior wall
- Posterior column
- Posterior column-posterior wall
- Transverse fractures
- Kocher-Langenbeck except if the fracture line crosses the acetabulum from proximal anterior to distal posterior and the displacement is greatest anteriorly choose the ilioinguinal approach
- Transverse-posterior wall fractures, T shaped fractures
- Kocher-Langenbeck unless the fracture looks very difficult in which case the extended iliofemoral approach may be used
- Both column fractures
- Ilio-inguinal unless the fracture looks very difficult in which case choose the extended iliofemoral approach
A couple of points on reduction techniques
- Specific instruments are available to ease reduction and fixation.
- A Schanz pin inserted into the femoral neck can ease distraction of the femoral head.
- A Schanz pin into the posterior column is useful in the many cases of posterior column fractures where there is a rotational deformity.
- Farabeuf clamps are used with small screws drilled into each segment and provide significant reducing power
- Consider using intraoperative fluoroscopy to avoid intraarticular screw placement.
- Difficult transverse posterior wall fractures
- if they include a transverse transtectal component
- if there is an extended posterior wall fracture involving the posterior border of the bone
- if they consist of T-shaped and posterior wall fractures
- if they are associated with dislocation of the pubic symphysis or fracture of contralateral pubic ramus
- Difficult T-shaped fracture
- Tranverse transtectal component
- those with wide separation of the vertical stem of the T
- those associated with pubic symphysis disruption or contralateral pubic ramus fracture
- Difficult both column fractures
- complex fracture of posterior column
- displaced fracture line crossing the sacroiliac joint,
- wide separation of the anterior and posterior columns at the rim of the acetabulum
- Wound infection
- Rates are higher if there is associated bowel or vaginal injury
- Higher if there is significant degloving. Degloving over the greater trochanter is known as a Morel-Lavale lesion. These injuries are frequently infected (46% rate of positive cultures)
- Nerve palsy
- Higher rate in the Kocher-Langenbeck approach
- Sciatic nerve affected, usually peroneal branch
- Attempt to always keep the knee flexed 60 degrees
- Femoral nerve may rarely be affected by a spike of bone from an anterior column fracture
- Heterotopic ossification
- Highest rate is with extended iliofemoral approach (57%), then Kocher-Langenbeck approach (26%). Very uncommon after ilio-inguinal approach.
- Other factors associated with HO are male sex, associated head or chest trauma, high ISS, T-shaped fractures
- Decrease rate with indomethacin 25mg TDS for six weeks postoperatively, or with 800 Gy of radiation within 72 hours postoperatively. A recent low powered RCT in the JBJS (Burd et al) showed no significant difference between the two regimens. Against the use of indomethacin is Matta’s 1997 RCT on the use of indomethacin vs. no prophylaxis which concluded that Indomethacin is not effective in preventing HTO
- If HO is extensive it can be removed at 15-18 months post surgery, with an expectation of around 80% of normal motion at this time
- HO sometimes spontaneously regresses
- Thromboembolic disease
- 33% in pelvic veins on one MRI study
- 61% in patients receiving no prophylaxis
- PE in 10%, fatal PE in 2%
- If a DVT is diagnosed prior to OT a caval filter should be inserted.
- Mechanical pumps may be the answer to perceived problems about blood loss from anticoagulants. These maintain venous flow and stimulate endogenous fibrinolytic activity. Pulsatile mechanical compression may be superior to low pressure sequential mechanical compression devices
- 3-4% overall
- The incidence is related to the time to reduction
- Blood loss
- Highest with extended iliofemoral (1.6L in Matta’s study)
- Lowest with Kocher-Langenbeck (900mL)
- Occurs within 5 years in 15-45% of patients (OKU7).
- Arthritis is delayed for 10 years or more with an excellent reduction.
Possible sequelae of acetabular fractures
- Post traumatic osteoarthritis
- Acetabular non-union
- Leg length discrepancy
- Nerve palsy
Measurement of outcomes
- Matta’s classification of reduction on postoperative radiographs is:
- Anatomic 0 to 1mm of displacement
- Imperfect 2 to 3mm of displacement
- Poor Greater than 3mm displacement
- Timing of Intervention
- Fractures treated after 21 days are more difficult to reduce and have poorer outcomes.
- Letournel’s large series of 569 fractures treated within 21 days demonstrated clearly that anatomical reduction is essential for long-term success.
- If anatomical reduction was achieved 90% of patients had a good result, but this ideal was achieved in only 74% of cases.
- At a 20-year followup 28 of 35 cases initially graded as excellent remained excellent.
- Type of Fracture
- In Matta’s study the outcomes were related to the type of fracture
- He was able to achieve an anatomical reduction in 96% of the simple fracture types but only 64% of the associated fracture types.
- There was no statistically significant relation to the degree of initial displacement, but there was a trend towards worse results with greater displacement
- Posterior wall fractures
- Posterior wall fractures can often be anatomically reduced but the results do not reflect this
- eg 94% of Letournel’s posterior wall fractures were anatomically reduced but only 82% had a good or excellent result
- Many posterior wall fractures are associated with posterior hip dislocations, and these have a high rate of AVN.
- Age of Patient
- Older patients (>40) have a lesser chance of an anatomical reduction.
- Abductor strength
- related to the approach;
- ilioinguinal approaches (89% normal abductors) were better than Kocher-Langenbeck (85%) and extended iliofemoral (66%).
- 1% of all fractures
- Lateral tibial plateau 70%
- More common as knees in valgus & forces usually cause valgus
- Medial plateau is involved in isolation in around 15%
- Bicondylar fractures occur in 15%.
- High violence injuries in young patients
- Indirect forces
- Axial loading
- Age and bone quality determine fracture pattern
- Younger patients develop split, older get depression
- Younger patients have higher rate of ligamentous injury (i.e., on opposite side)
- Older patients compact subchondral cancellous bone
- ligamentous injuries
- popliteal artery injury
- neurologic injury (esp peroneal nerve)
- compartment syndrome
- Medial tibial plateau
- concave from front to back & from side to side
- medial plateau is stronger than lateral, so injury here is more rare & is accompanied by more soft tissue damage
- Lateral tibial plateau
- convex from side to side & front to back.
- lateral meniscus covers larger area than medial
- Type I Split of lateral plateau
- seen in young people with strong bone
- Often associated with tear of lateral meniscus, which is trapped in fracture.
- Type II Split depression fracture
- Caused by valgus blow with axial loading
- Typically occurs in patients older than 40
- Type III Pure depression (die punch) of lateral tibial plateau
- Central depressions are usually more stable than lateral or posterior.
- Type IV Fracture of medial tibial plateau
- Much less common, associated with large forces.
- Often associated with lateral collateral ligament injuries
- Many of these injuries represent knee dislocation that has reduced.
- THIS IS FRACTURE PATTERN MOST ASSOCIATED WITH ARTERIAL INJURY.
- Type V Bicondylar fracture
- Usually result of pure axial load applied to knee
- hallmark of this injury is that at least small part of metaphysis remains as part of joint.
- Type VI Plateau fracture with complete dissociation of metaphysis from diaphysis
- A Extra-articular
- B Unicondylar
- C Bicondylar
- Need to carefully assess soft tissue injuries:
- # blisters, skin wounds, tenting of skin, vascular compromise
- detailed neurologic exam
- look for associated injuries
- more common with grades IV-VI
- compartment syndrome,
- neurovascular injuries,
- ligamentous injuries
- AP, lateral, oblique images
- Opposite knee can serve as useful template
- Look for subchondral bone below articular surface
- Can do 15° caudal plateau views, obliques
- Stress radiographs may be used if considering non-operative
- ** the medial plateau is concave, the lateral plateau is convex (in both planes)
- the lateral plateau is also higher than medial,
- can help identify meniscal pathology;
- use particularly in type I fractures & or those in which percutaneous fixation is contemplated.
- Depends on soft tissues
- Skin compromised = Ext fix
- open fractures require I & D
- grade 2 & 3 open fractures probably best treated with temporary ex fix & late reconstruction of articular surface or ring fixator & mini-open arthrotomy to reduce articular surface
- may require plastic surgery – usu rotational muscle flap in this location (gastroc)
- Hinged knee brace can be used for minimally displaced, or non-operative patients
- Non/partial weight bearing for 8-12 weeks
- open fractures
- compartment syndrome
- acute vascular injury
- Joint depression
- Acceptable amount not agreed upon
- < 3-5mm are normally quoted
- Long term followup has not demonstrated correlation between degree of depression & development of arthritis.
- of greater than 10° of nearly extended knee (varus /valgus) c.f. other side
- joint depression severe enough to lead to instability is predictive of poor result
- Tips & Tricks
- Either immediate before significant swelling or delayed to allow soft tissues to heal
- minimal stripping of comminuted fragments & careful soft tissue handling
- use periarticular large fragment plate laterally (types I/II/V/VI)
- use either anterior approach or 2 incision technique for bicondylar fractures
- bicondylar fractures need 2 plates (medial buttress plate)
- type IV fractures need buttress plate/screw rather than just interfragmentary screws
- almost always use ICBG
- use large fragment distractor to aid in reduction thru ligamentotaxis
- risk of infection (10-40%) & wound slough
- Submeniscal arthrotomy provides access to joint surfaces.
- Surgical treatment
- Type I
- percutaneous cannulated screws
- Type II
- ORIF with elevation, bone graft & lateral periarticular plate using hockey stick lateral incision.
- Type III
- can attempt to elevate via cortical window, bone graft & stabilize with couple of screws.
- Use arthroscope to assess adequacy of reduction
- Type IV
- percutaneous or open techniques
- Nonoperative management is associated with high rate of varus malunion.
- Types V & VI
- Combined Anterolateral & posteromedial incision
- Safest way to access bicondylar fractures
- Extensile midline anterior incision
- this can also be used in any subsequent knee replacement
- Schatzker describes doing Z cut of patellar tendon( tubercle osteotomy may be almost impossible to fix) & division of medial & lateral capsule below menisci, flapping whole up; done via midline incision. At end of procedure tendon is protected by tension wire or heavy suture
- In very severe fractures less injured condyle is fixed first.
- Can consider using one or two femoral distractors to help with indirect reduction of fracture.
- If hybrid external fixation is used wires should be placed no closer than 15mm to joint.
- Once bony parts of injury have been treated ligaments should be assessed. Any posterolateral injury should be addressed concurrently.
- external fixator
- spanning ex fix from femur to tibia to hold soft tissues out to length & maintain reduction
- half pins in femur & tibia
- best to align the articular surface early, with limited fixation
- once soft tissues have healed à ORIF
- ring fixator:
- mini-open reduction of articular surfaces using K-wires & small fragment screws
- fine wires at level of articular surface (at least 2) & half pins in tibia
- reduced deep infection rate & soft tissue complications
- is very rare, except in Schatzker VI injuries
- is common.
- If it is excessive & not responsive to aggressive physiotherapy adhesiolysis & MUA is indicated
- Infection (6 to 12%)
- Wound problems are the biggest problem in plateau fractures
- Important to respect soft tissues, etc
- Time surgery appropriately
- Concern with large elevations of skin (bicondylar plates)
- Loss of reduction
- Should use buttress plates, unless bone quality is very good
- Post traumatic arthrosis
- Cartilage damage from initial injury
- Also if residual joint incongruity
- Important to preserve the meniscus
- Avoid immobilization
- Union at the metaphyseal – diaphyseal junction can be a problem
- - 90% good/excellent results with ORIF (all types of fractures) – Lansinger et al., 1986 (seems too good to be true)
- Minimally displaced are expected to do well, even with non-operative
- Difficult to assess outcomes of displaced, as studies differ in classification, indications, etc
- Helpful that the lateral meniscus covers most of the plateau