- Considerations:
- see
plate fixation theory and bone healing with
plate fixation;
- most satisfying candidates for ORIF are humeral shaft frx w/ no comminution w/ enough of an oblique component to allow
lag screw fixation;
- in contrast, comminuted transverse fractures may be less satisfying for fixation, and may require bone grafting;
- w/ transverse fractures, lag screw fixation is not possible, and
plate prebending may be necessary;
-
biomechanical considerations:
- if pt has a stiff elbow, anterior cortex becomes the one under tension;
- in pts with a normal elbow, the posterior cortex is under tension;
- this would mean that in pts with a mobile elbow, the compression or tension band plates should be applied posteriorly,
and in pts with a stiff elbow, anteriorly;
- Proximal Third Humerus Shaft Frx: (see
proximal humerus fracture)
- in upper diaphysis the plate is most commonly placed on the antero-lateral surface of the bone; (see
anterior approach)
- in proximal portion of the shaft, where the bone flares to meet the metaphysis, the cortex is thin and very difficult to tap;
- if one inadvertently allows tap to wander, it can easily miss the hole or strip the thread;
-
spiral compression plate:
- goal of technique to avoid deltoid muscle stripping by twisting and contouring the plate along the proximo-lateral humerus and
along the distal-anterior aspect of the humerus;
- authors recommend using a skeletal template to contour the plate prior to surgery;
- proximally the plate is applied on the lateral surface of the greater tuberosity, and more distally the plate crosses anteriorly
between the pectoralis major and the deltoid insertion and ends up lying on the anteiror surface of the humeral shaft;
- the contour of the proximal aspect of the plate misses the bicipital groove (by coursing lateral to it);
- ref: The spiral compression plate for proximal humeral shaft non union: a case report and description of a new technique.
DRJ Gill and ME Torchia.
Journal of Orthopaedic Trauma.
Vol 13. No 2. 1999. p 141.
- Mid Humeral Shaft Frx:
- plate selection: (
Synthes Humeral Shaft Implants)
- becuase of the large
rotational forces placed on the humerus, it is best to use a broad 4.5
DCP or
LC-DCP w/ staggered screw holes;
- this increases distances between successive screws & decreased likelihood of fissuring the bone longitudinally;
- use of standard 4.5 plate is less optimal for resisting these forces;
- in oblique frxs,
4.5 mm cortex screws can be inserted first as
lag screws outside of the plate or thru the plate;
- plate position:
-
posterior approach:
- generally, frxs of the mid-shaft and distal humerus should be placed posteriorly;
-
radial nerve:
- careful to avoid injury to the radial nerve;
- as noted by
Gerwin et al, nerve crosses posterior aspect of humerus at 20-21 cm proximal to medial epicondyle and 14-15 cm proximal to lateral epicondyle;
- alternatively the nerve can be found a distance equal to the length of a 8 hole Synthes DC plate above the olecranon fossa;
- with plate fixation, the nerve will generally end up lying on the surface of the plate;
- with humeral fractures across the spiral groove, there is the option of radial nerve transposition;
- references:
-
Radial nerve transposition with humeral fracture fixation: preliminary results.
-
Anterior radial nerve transposition in humerus midshaft fractures: anatomic and clinical study.
-
frx reduction:
-
lag screw insertion is the easiest technique to achieve reduction;
- w/ fracture comminution consider need for
BMP patch or consider fracture shortening (inorder to maximize cortical opposition);
-
plate application:
- distal humerus flares in the coronal plane, allowing easy application of
broad 4.5 plate over the posterior humeral surface;
- broad plate allows better rotational stability;
- in the saggital plane the distal humerus narrows, and therefore, application of the broad plate over the anterolateral
surface may be difficult (note that 4 screws must be inserted distal to the fracture);
-
anterior approach:
- some surgeons, however, favor anterior approach for mid-shaft fractures inorder to avoid injury to
the
radial nerve which lies in posteriorly in the spiral groove;
- inorder to achieve fixation w/ 4 screws above the frx, the plate will often have to come to rest underneath of radial nerve;
- hence, the anterior approach is generally favored for humeral frxs of the proximal and mid diaphysis w/ the
plate applied to the anterolateral surface of the humerus;
-
examples:
*** 
- Distal Humerus:
- frxs of distal 2/3 of the humeral shaft should be placed posteriorly (see
posterior approach to humerus);
-
4.5 DCP;
-
3.5 mm DC plates should be used only in the supracondylar area;
- two
3.5 mm recon plates extending down supracondylar ridges gives good purchase on short distal fragment;
-
example:
- Complications:
-
non-union: approximately 5%;
- infection: most often occuring in open fractures;
Open reduction and internal fixation of humeral shaft fractures. Results using AO plating techniques.
Plate fixation of the humeral shaft for acute fractures, with and without radial nerve injuries.
The results of plating humeral shaft fractures in patients with multiple injuries.
MJ Bell, CG Beauchamp, JK Kellam, RY McMurtry.
JBJS 67-B, 1985. p 293-296.
Internal fixation of fractures and non-unions of the humeral shaft: Indications and results in a multi-center study.
RJ Foster, GL Dixon, AW Bach, RW Appleyard, TM Green.
JBJS 67-A, 1985. p 857-864.
Compression plating versus Hackethal nailing in closed humeral shaft fractures failing nonoperative reduction.
EC Rodrigruez-Merchan.
J. Orthop. Trauma, Vol 9. 1995, 194-197.
Radial nerve transposition with humeral fracture fixation: preliminary results.
The treatment of humeral shaft fractures. Results of a prospective AO multicenter study.
