Synthes MultiLoc Proximal Humeral Nail User manual

MultiLoc Proximal Humeral Nail.
Proximal humeral nail with multiple
locking options for simple and complex
fractures.
Technique Guide

Introduction
Surgical Technique
Product Information
Image intensifier control
MultiLoc Proximal Humeral Nail Technique Guide Synthes
Table of Contents
MultiLoc Proximal Humeral Nail 2
Screw Configuration 4
AO Principles 5
Indications 6
Clinical Cases 7
Patient Positioning 10
Approach 11
Opening the Humerus 13
Nail Insertion 16
Nail Positioning 18
Proximal Locking 22
MultiLoc Screws 22
3.5 mm Locking Screws 26
Distal Locking 30
End Cap Insertion 34
Implant Removal (Optional) 37
Implants 40
Instruments 45
Set Lists 54

MultiLoc Screws
1Blunt screw tips to minimize the risks
associated with secondary screw
perforation
2Countersunk screwheads to reduce
implant prominence
3Four suture holes per screw, for
attachment of the rotator cuff muscles
4Option for secondary 3.5 mm locking
screws, for improved stability where
needed*
MultiLoc Proximal Humeral Nail.
2 Synthes MultiLoc Proximal Humeral Nail Technique Guide
Proximal humeral nail with multiple locking options for
simple and complex fractures.
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MultiLoc Proximal Humeral Nail
– Cannulated nails in right and left
designs, 8.0 mm and 9.5 mm diame-
ters, and 160 mm length, to ensure
optimal fit in the canal
– Straight nail for central insertion
point, to avoid potential insertion
through the fracture site, increasing
biomechanical stability
Angular Stable Locking System ASLS
(optional)
Improved fixation in poor bone quality.
MultiLoc Proximal Humeral Nail Technique Guide Synthes 3
* Comparative testing was conducted by Synthes
with the MultiLoc Humeral Nail construct
implanted in polyurethane foam block material of
multiple densities. Static bend testing was
conducted to compare the stability of the nail
construct with and without the secondary 3.5 mm
locking screws assembled with the proximal
lateromedial (LM) screws. The static bending force
was applied to the test constructs in an eccentric,
mediolateral direction.Testing was conducted with
the test sample constructs implanted in foam block
material with densities of 5.5 pcf (pounds per
cubic foot), 7.5 pcf, and 10 pcf. Failure was
defined as varus collapse of 10 mm or cutout of
the proximal screws. Results showed as much as a
45% increase in construct stability when the
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– Ascending screw option to provide
support to the calcar
– Multiplanar distal locking options for
less implant toggling in the medullary
canal
– Fully targeted locking options for
accurate screw insertion
– Polyethylene inlay for secure screw
fixation
secondary 3.5 mm locking screws were assembled
with the proximal LM screws and the construct
was subjected to the static mediolateral bending
force. Test results showed that in 10 pcf foam
material, the MultiLoc Humeral Nail construct
failed at 315 N (mean) with secondary locking
screws assembled with LM screws vs. 230 N
(mean) without secondary locking screws. In 7.5
pcf foam material, the construct failure occurred at
141 N (mean) with secondary 3.5 mm locking
screws vs 123 N (mean) without secondary 3.5 mm
locking screws. In 5.5 pcf foam material, the
construct failed at 137 N (mean) with secondary
3.5 mm locking screws vs. 94 N (mean) without
secondary 3.5 mm locking screws.

4 Synthes MultiLoc Proximal Humeral Nail Technique Guide
A
B
C
D
E
F
G
* Comparative testing conducted by Synthes with the MultiLoc Proximal Humeral
Nail construct implanted in polyurethane foam block material of multiple densities.
Testing compared the stability of the nail construct with and without secondary
3.5 mm locking screws assembled with the proximal lateral screws. Results
showed as much as a 45% increase in construct stability when the secondary
3.5 mm locking screws were assembled with the proximal lateral screws and the
construct was subjected to a static mediolateral bending force. Bench test
results do not necessarily reflect clinical performance.
Proximal locking: Levels A to D
The three lateral screws (greater tuberosity, levels A, B, and
D) must be used in any fracture situation, as they ensure the
basic stability of the construct.
Screw type:
– 4.5 mm Titanium MultiLoc Screws (gold)
The anterior screw (lessor tuberosity, level C) increases the
stability of the construct. It may be used in fractures with a
lesser tuberosity fragment if the fragment is large enough
to accommodate the screwhead. Do not insert a 3.5 mm
locking screw in this location.
Screw type:
– 4.5 mm Titanium MultiLoc Screws (gold)
Additional locking screws (greater tuberosity, levels A, B,
and D) may be inserted through the screwheads of the
lateral screws, to increase stability of the osteosynthesis.
These locking screws are aimed posteriorly where increased
bone density may be present. These additional screws may
be especially useful in osteopenic bone.*
Screw type (optional):
– 3.5 mm Titanium Locking Screws (green)
Ascending screw: Level E
The ascending screw supports the medial calcar region which
can be helpful in medially comminuted fractures.
Screw types:
– 4.0 mm Titanium Locking Screws (blue)
– 4.0 mm Titanium ASLS Screws (brown; optional)
Distal locking: Levels F and G
The two distal locking screws are located in different
planes to reduce implant toggling in the humeral canal,
compared to monoplanar locking.
Screw types:
– 4.0 mm Titanium Locking Screws (blue)
– 4.0 mm Titanium ASLS Screws (brown; optional)
Screw Configuration

1. M.E. Müller, M. Allgöwer, R. Schneider, and H. Willenegger.
Manual of Internal Fixation, 3rd Edition. Berlin: Springer-Verlag. 1991.
In 1958, the AO formulated four basic principles, which
have become the guidelines for internal fixation.1They are:
Anatomic reduction
Fracture reduction and fixation to restore anatomical
relationships.
Stable fixation
Stability by fixation or splintage, as the personality of the
fracture and the injury requires.
Preservation of blood supply
Preservation of the blood supply to soft tissue and bone
by careful handling.
Early, active mobilization
Early and safe active mobilization of the part and patient.
AO Principles
MultiLoc Proximal Humeral Nail Technique Guide Synthes 5

6 Synthes MultiLoc Proximal Humeral Nail Technique Guide
The MultiLoc Proximal Humeral Nail is indicated for fractures
of the proximal humerus, including:
– 2-part surgical neck fractures
– 3-part fractures
– 4-part fractures
Indications

MultiLoc Proximal Humeral Nail Technique Guide Synthes 7
Clinical Cases
Case 1: 2-part surgical neck fracture
78-year-old woman. Simple fall.
Treatment with:
– 8.0 mm MultiLoc nail
– 3 MultiLoc screws (levels A, B, and D)
– Standard distal locking
Preoperative, AP view Postoperative, AP view
Preoperative, scapular Y-view Postoperative lateral view
*Results from case studies are not predictive of results
in other cases. Results in other cases may vary.

Clinical Cases
Case 2: 3-part fracture
53-year-old woman. Simple fall, after 6
weeks of conservative treatment with
severe pain and impossible active
rehabilitation. Treatment with:
– 9.5 mm MultiLoc nail
– 3 MultiLoc screws (levels A, B, and D)
– 3.5 mm locking screw (screw-in-screw)
(level A)
– Ascending screw with ASLS
– Distal locking with ASLS
8 Synthes MultiLoc Proximal Humeral Nail Technique Guide
Preoperative, AP view Postoperative, AP view
Preoperative, scapular Y-view Postoperative lateral view