Patient Communication

Effective communication regarding challenges that may be encountered is paramount. Any discussion should include:

1. Discussion of outcomes and possible complications.
2. Pain management options.
3. A realistic timeline of frame wear.
   
   Orthopedic fractures	12–16 weeks
   Orthopedic fracture with compromised host (DM, PVD)	20–24 weeks
   Charcot Reconstruction	24 weeks minimum
   Smoker or Tobaccco use	double the time in fixator
4. Psychological considerations
5. Photos or models of representative external fixators, setting patient expectations prior to emerging from the OR.

Frame Size Selection

The circular external fixator is constructed with no less than 2.0 cm of distance between the skin and the inside diameter of the ring, ensuring adequate stability of the bone segments. If additional clearance to the skin edges is needed, coning or funneling of the fixator rings is needed without compromising bone stability.

Ring and Pin Placement

While there are myriad application techniques and constructs possible, several pearls warrant mention regardless of the aparatus chosen.

Note: Proper soft tissue management throughout the procedure is a primary concern. Soft tissues should be released and retracted during insertion of transosseous wires and half pins, preventing soft tissue irritation [2, 6].

1. Proximal ring: The double laser line on the proximal ring should be aligned parallel with the tibial crest, 4 cm distal to the tibial tuberosity (Figure 1).
2. Proximal half-pin: Placed 10–15° oblique to the medial surface of the tibia, in the direction of the diaphysis of the bone (Figure 1).
3. Transosseous wires: Mounted above and below the same ring at a 60° angle, relative to the opposing wire or half pin, laterally (Figure 2) [4].
4. Simultaneous wire tensioning: Allows uniform tension across the length of the wire and ring, preventing instability (Figure 3) [5].
5. Leg fully extended, ankle dorsiflexed to 90°: Limb positioning minimizes post-operative stress on soft tissues caused by transosseus wire and half pin placement.
6. Avoid thermal trauma to the tissues: Wires and pins are placed in cold sterile water prior to use (Figure 4). K-wires are pulsed, rather than drilled on the “constant” setting while grasping the wire with a wet sponge (Figure 5) [6].
7. Dressing: Transosseous wires and half-pins are dressed in the OR with 4 × 4 gauze, cut in the center, and saturated in isopropyl alcohol. the entire construct is dressed with Kerlix and an ACE bandage, with a modified surgical shoe secured to the bottom of the fixator by bandage or Zip tie.

Pain management

Patients are discharged on a multimodal pain management protocol [7, 8, 9].

Tramadol 50 mg, TID

Gabapentin 100 mg, TID

Acetaminophen 500 mg, TID

The combination of Tramadol, Acetaminophen, and Gabapentin work synergistically together to reduce/eliminate the need for schedule 2 opiates post-operatively. Patients gradually reduce the dosages over the course of 2–4 weeks.

Weight Bearing

The ability to bear weight immediately offers a practical advantage over other modalities [10]. Patients are advised 20% weight-bearing, best explained as gentle touchdown, stabilizing the limb while ambulating with a walker or crutches. Once initial incisions have healed, our protocol increases weight bearing on the limb as tolerated.

It is important to remember that consistent weight bearing increases the forces around the wire, ring and limb. Therefore, the practitioner must ensure the tightness and the tension of the wires to construct at every clinical visit.

Pin Care

Pin site complications range from 0% to100% [2, 11, 12], with the majority of complications noted as “infection”. This broad range is problematic, due in part to the lack of a universal classification and optimal pin care protocols [2, 6, 11, 12, 13, 14].

Our classification is based on the algorithm devised by Checketts (2000) [15] and modified with subtle procedural guidelines:

Grade 1: Pin Tract Irritation

1. If wire is loose, re-tension
2. Soft tissue involvement receives local treatment and/or soft tissue release

Grade 2: Pin tract irritation with drainage

1. Grade 1 interventions
2. Oral antibiotics

Grade 3: Erythema >2 cm radius from pin with drainage and low grade constitutional symptoms

1. Grade 1 interventions
2. IV antibiotics

Grade 4: Erythema >2 cm radius, with drainage and radiographic evidence of localized osteolysis

1. Pin removal

Grade 5: radiographic osteolysis with soft tissue infection

1. Pin removal with surgical debridement

Grade 6: Suspected osteomyelitis

1. Radiologic and imaging confirmation with possible bone resection

Overall, pin-tract irritation is expected and should not initially be considered a complication [6, 10, 13]. infection is emergent when erythema, edema and induration exceed 2.0 cm around the perimeter of a given pin site. In these instances, patients begin a 3-to-4-day course of oral antibiotics and should undergo flouroscopy. If lucency is noted around the osseous portion of the wire or pin, the wire is removed and a bone resecton in the operating theatre is scheduled. If osseous structures are normal, the local pin site is adequately treated and the surgeon re-tensions the loose wire.