Surgical Viva Flashcards
Explain surgical approach used for a closed distal end radius fracture?
I would perform a modified Henry’s approach at the volar aspect of distal third radius to enable me to perform open reduction and internal fixation (using palmar LCP) to the distal end radius fracture.
Ulnar fixation:
If there is gross instability on DRUJ assessment (after comparing with contralateral side) after the fixation of the radial fracture, it is recommended that the styloid and/or the triangular fibrocartilaginous disc (TFC) is reattached.
Steps:
1. Patient is placed supine with affected upper limb placed on an arm board which is radiolucent.
2. Well-padded tourniquet is placed on the arm.
3. Affected upper limb is cleaned and draped.
*Preliminary CMR is performed, fracture stabilised temporarily with K-wires to aid with fixation later.
4. Using the modified Henry’s approach at the volar aspect of distal third radius to gain access to the fracture site.
- landmarks: distally (FCR tendon), proximally (bicep tendon insertion)
- longitudinal incision that begins proximal to distal crease of wrist, just at and along the radial border of the FCR directed towards the bicep tendon, with overal lenght spanning across the distal radius fracture with lenght equal to estimated palmar plate lenght.
4. Subcutaneous layer and sheath following that is opened up.
- Using the plane between flexor carpi radialis tendon and the radial artery, deep dissection is performed untill the pronator quadratus is seen, taking care not to damage the radial artery and the palmar cutaneous branch of the median nerve which are at risk during this approach.
At this point
the radial side - radial artery
the ulnar side - palmar cutaneous branch of the median nerve, median nerve, FPL.
These structures are retracted away gently
- Deepen the interval between the FPL and Radial Artery using finger untill Pronator Quadratus is seen.
- Dissection of the PQ
- is through elevation using an L-shaped incision, where the horizontal limb is placed at the watershed line (few mm proximal to the joint line; the position of the joint line can be determined by a hypodermic needle placed in the joint).
- The PQ is incised on its radial border, exposing the distal radius. It is stripped off the distal radius together with the periosteum using periosteal elevator. - Fracture site is visualised for actual pattern. If preliminary reduction has been performed with K-wires in placed to hold reduction, confirm again with II. If none done, priorities in fracture reduction in distal radius are:
i) accurate anatomic reduction of the articular surface.
ii) restoration of the acceptable radial height.
iii) restoration of volar tilt/neutral (make sure no dorsal tilt). - Palmar plate used- Variable angle LCP.
- Ensure adequate lenght spanning the fracture site.
- Ensure no overhanging of plate at radial and ulnar border of the radius.
- Ensure distal screws does not end up in the radiocarpal joint.
- The distal end of the plate should end at the anatomic watershed zone of the distal radius.
i) I would start with inserting a screw through the oblong plate hole in the proximal radial fragment. Select a screw which is long enough to engage both cortices.
ii) I would adjust my plate accordingly, making sure the distal end of the plate should end at the anatomic watershed zone of the distal radius, whist there is adequate screws for proximal segment of the fracture, and no overhanding of plate over radius, before tightening of this screw.
iii) Then i will insert distal screws, begining with ulnar sided screw hold.
Why? if the initial screw is placed on the radial side it will block accurate imaging of the ulnar screw placement.
iv) With every insertion of the screw, a sagittal image is obtained with the angle of the X-ray beam directed 20° obliquely to the radius to confirm that the screw is not penetrating the radiocarpal joint.
v) Finally i will insert the proximal screws, with atleast 2 screws, ideally 3.
vi) I will check stability of my fixation.
vi) I will also check stability of the DRUJ. If this is compromised, I will perform a closed reduction transfixion of the two bones using K-wire transfixion proximal to the DRUJ. It is recommended to insert the K-wire(s) in the position of the forearm in which the ulnar head proves to be most stable. K-wire is maintained temporary (3-4 weeks). Stability is usually in a neutral or supinated position, except in the rare cases of anterior displacement of the ulnar head. Most surgeons recommend cast or brace splintage of forearm rotation (Sugar Tong) during the period of K-wire transfixion.
vi) I will also consider fixing the ulnar styloid with either an intramedullar screw (if fragment big) or K-wire (if fragment is small).
Explain surgical approach to the injury seen in the plain radiograph.
My aims for this fracture are - anatomical reduction and stable fixation of the diaphyseal radius fracture. - ensure reduction and stability of the DRUJ - ensure no other fractures along the radius, ulnar, carpal bones or elbow dislocation present (for which I will perform additional radiographs to ensure prior to surgical treatment). If no other injuries are present, I will plan for ORIF of the radius KIV for K-wire of the DRUJ. Anatomical reduction and fixation of the radial fracture usually lead to spontaneous reduction of the distal radioulnar displacement. I will assess the DRUJ (with comparison to the contralateral normal side) after I have performed fixation of the radius.
Surgical steps:
Steps:
- Patient is placed supine with affected upper limb placed on an arm board which is radiolucent.
- Well-padded tourniquet is placed on the arm.
- Affected upper limb is cleaned and draped.
- Using the modified Henry’s approach at the volar aspect of middle radius (directly above the fracture site) to gain access to the fracture site. - landmarks: distally (FCR tendon), proximally (bicep tendon insertion) - longitudinal incision over the fracture site, along an imaginary line from the radial styloid directed towards the bicep tendon.
- Deep dissection is in the plane between brachioradialis (laterally) and pronator terest (medially). Pronate the forearm fully to identify the lateral edge of the pronator teres and its insertion, then mobilise & retract the PT and FDS medially and retract the brachioradialis laterally. Then perform subperiosteal elevation of FPL origin.
- At fracture site
- Identify the distal and proximal fracture ends.
- Clear soft tissues between fracture ends.
- Making sure no overstripping of periosteum.
- Perform open reduction of fracture ends to get anatomical reduction. - Plating
- Choose small DCP with 6-8 holes, depending on fracture length, to ensure 3 screws proximal and distal to fracture can be placed.
- If transverse/ short oblique pattern, can use compression plating technique to achieve interfragmentary compression at fracture site to allow primary bone healing.
- Check screw length adequate using II. - Check DRUJ - After fixation of the radius, check the position of the ulnar head throughout the range of forearm motion. Stability is tested manually by rotating the forearm from pronation to supination whilst palpating the ulnar head.
If head reduced, Unstable:
Additional stabilization is recommended using K-wires, where after determining in which rotational position the DRUJ is restored, a temporary K-wire transfixation of both bones in rotational position of maximal stability (a neutral position or in supination) is inserted slightly proximal to DRUJ and maintained for 3-4 weeks postoperatively and forearm rotation prevented by appropriate casting.
If head irreducible:
Consider open reduction and exploration. immediate exploration of the DRUJ is necessary to deal with any ligamentous interposition or other obstruction (tendon).
With posterior dislocations of the ulnar head, very occasionally the extensor carpi ulnaris tendon can become entrapped.
The approach chosen (whether anterior or posterior) depends on the direction of the displacement of the ulnar head.
A) Posterior approach for posteriorly dislocated ulnar head.
i) The posterior approach to the DRUJ is via the interval between the 4th and 5th extensor compartments.
ii) Gently retract the displaced ulnar head in order to inspect the interior of the joint for interposed soft-tissue or cartilage fragments.
iii) Clear the joint, reduce the ulnar head, usually by supination, and suture the torn edges of the articular capsule using interrupted resorbable sutures.
iv) To avoid any redislocation
- immobilization of the forearm in the rotational position of maximal stability is usually achieved using a cast or a removable brace that controls forearm rotation.
- temporary transfixation with K-wires.
B) Anterior approach for anteriorly dislocated ulnar head.
To approach the DRUJ from the anterior aspect involves considerable deep dissection between important anatomical structures and should be avoided if possible. Fortunately, anterior dislocation of the ulnar head is rare.
If the anterior approach to the radial fracture can be extended distally without major further dissection, the DRUJ can be approached in this manner, elevating pronator quadratus. By retracting the dislocated ulnar head, a limited view into DRUJ is possible and this may suffice for removal of interposed soft tissue.
If have to do, reduce the ulnar head; this is usually achieved by pronation. It is not usually possible to suture the torn ends of the articular capsule.
