RECONSTRUCTION OF
DELAYED UNION AND NONUNION OF THE PROXIMAL ULNA AND OLECRANON
Chaitanya
S. Mudgal, MD, and Jesse B. Jupiter, MD
Delayed and / or nonunion of the proximal ulna and the
olecranon is extremely uncommon. However, the degree of upper limb dysfunction
can be profound. Nonunion has been identified in 5 per cent of all olecranon
fractures.
Delayed or nonunion of the proximal ulna and olecranon can limit elbow
mobility resulting in inhibition of the ability of the upper limb to place the
hand within the volume of a sphere in space. Since the volume of a sphere is
proportional to the cube of its radius, any loss of elbow motion leads to a
significant loss of reach of the hand.
A fracture of the proximal ulna should be considered to be ununited if
there has been no radiographic evidence of union after 6 months. The presence
of a displaced or angulated fracture with no clinical or radiographic signs of
union with or without the presence of loose or failed hardware, constitutes a
nonunion. A delayed union may be considered if there has been some early
attempts at union which then seem to have plateaued or the radiographic
progress of union is not commensurate with the time period since the fracture.
Irrespective of the definitions of each of these terms, it is optimal to
identify a delay in healing and prevent it from developing into a well defined
nonunion. The management of a delayed union is similar in numerous aspects to
the management of nonunion in this location and as such, these two entities are
addressed as one.
A nonunion in this location is often associated with pain, stiffness
affecting both the ulnohumeral and forearm articulations, and occasionally
instability of the ulnohumeral joint.
Infection should also be considered as a cause of nonunion.
The multiply operated elbow increases the risk of underlying infection and this
will need to be addressed aggressively, if union is to be achieved.
A stable painfree elbow and forearm are vastly superior to an
arthroplasty and every effort should be made to achieve union, when possible.
While there is no chronological age demarcation in the decision making process,
alternative methods of management may be considered in the elderly.
In patients who have a dysfunctional upper limb due an olecranon or
proximal ulnar nonunion, reconstruction with osteosynthesis should be
considered, provided they are able to comprehend and follow the treatment and
rehabilitation process, have a sensate hand, and functioning motors of adequate
strength about the elbow.
The primary goal of reconstructive surgery is both, achievement of bony
union as well as restoration of a functional range of motion. The requirements
to achieve these goals will be a stable, pain-free, concentric elbow, with
congruous articular surfaces, and an intact functioning extensor mechanism and
soft tissue envelope.
In the decision making process, several factors play an important role.
These are called the Ôcritical factorsÕ and include (a) symptoms, (b) the
physiologic age of the patient, (c) the functional abilities and demands of
both the patient as well as the affected upper limb, (d) the condition of the
soft tissue envelope and extensor mechanism, (e) the size and condition of the
proximal fragment as well as the condition of any existing implants, (f) the
condition of the articular surface especially following comminuted articular
fractures, (g) co-existent problems which may need to be addressed at the time
of the reconstruction such as heterotopic ossification, radio-ulnar synostosis,
and stiffness and finally (h) the presence of infection. The presence of
infection or a poor soft tissue envelope or both may require multiple
procedures prior to undertaking a formal bony reconstruction.
This paper outlines the rationale, clinical approach and
surgical tactic for the management of proximal ulnar and olecranon nonunions.
Published by the New England Hand Society 2005.