Aseptic necrosis of the metacarpal head was first reported
by Dieterich1 in 1932. This is
an uncommon problem, and there are only a few isolated case reports
in the literature2-5. The symptoms
range in severity; some patients are asymptomatic, while others
have a complete collapse of the metacarpal head with a painful and
restricted range of motion of the metacarpophalangeal joint6. Because of the limited experience
with this problem, no single modality of treatment can be recommended
as ideal.
In this report, we describe the case of a patient with changes resembling
avascular necrosis of the head of the third metacarpal of the right
hand. This problem was treated by a flexion osteotomy of the metacarpal
neck, which led to an improvement in function. Our operative technique
and the clinical and radiographic results are also discussed.
A sixteen-year-old right-hand-dominant male student presented
with a one-month history of pain in the region of the right third
metacarpophalangeal joint and limitation of flexion. There was no
history of any predisposing systemic illnesses or steroid use. Despite
his participation as a member of the high-school basketball team,
the patient could not recall any specific incident of trauma to
the metacarpophalangeal joint.
Clinical examination of the right third metacarpophalangeal joint
revealed no signs of erythema, warmth, or swelling. An asymmetrical
osseous prominence of the metacarpal head was noted. The range of
motion of the involved joint was 60° of flexion with an extension
lag of 20°. Both active and passive movement of the joint was painful.
Grip-strength measurements demonstrated 30 kg of force on the right
compared with 47 kg on the uninvolved side. Screening tests were
negative for signs of systemic infection or rheumatological conditions.
Radiographs revealed flattening of the metacarpal head with cystic
lesions and sclerosis (Figs. 1-A and 1-B). T1-weighted magnetic resonance
images demonstrated an area of low signal intensity, suggesting
ischemic changes. Radionuclide bone imaging showed an area of intense, increased
uptake at the metacarpal head.
The patient was treated initially with nonsteroidal anti-inflammatory
medication, and he was advised to limit his participation in sports.
However, the symptoms continued to progress until even activities
such as writing and the use of chopsticks became painful.
An arthroscopy was performed with use of an axillary block. A
1.9-mm arthroscope was inserted through dorsal portals at the level
of the metacarpophalangeal joint on either side of the extensor
digitorum communis tendon. Inflamed synovial tissue was debrided
with a suction punch. The metacarpal head showed erosion of the
articular cartilage in the center. The cartilage on the dorsal aspect
of the metacarpal head was preserved with only minimal changes in
its quality. The articular cartilage of the proximal phalanx was
normal.
The metacarpal head and neck were exposed subperiosteally through
a 1-in (2.5-cm) dorsal longitudinal skin incision, and an osteotomy
was performed through the neck at the level of the metaphysis. The
osteotomy site was gently opened dorsally until the healthy cartilage
on the dorsal aspect of the metacarpal head was aligned with the
cartilage of the proximal phalanx. The volar flexion osteotomy site
was kept open by a corticocancellous bone graft harvested from the
distal aspect of the radius. To stabilize the osteotomy site, three 0.064-in
(0.163-cm) Kirschner wires were driven under fluoroscopic guidance
from the base of the metacarpal head across the osteotomy site.
The hand was immobilized in a short-arm plaster cast for six weeks.
At the end of this period, radiographs confirmed healing of the
osteotomy site. The pins were removed, and range-of-motion exercises
were begun. Three months after the operation, the patient was able
to resume playing basketball without pain or limitations.
At the four-year follow-up evaluation, the patient had a painless
range of motion of the metacarpophalangeal joint, with 80° of flexion
and a 10° extension lag. Grip strength had improved slightly, to
34 kg. Radiographs revealed complete healing of the osteotomy site.
There was no evidence of sclerosis or of cystic changes in the metacarpal
head, but slight incongruity of the metacarpal head persisted (Figs. 2-A and 2-B).
Magnetic resonance imaging at forty-six months after the operation
revealed a reduction in the area of the low-intensity signal, suggesting
an improvement in the vascularity of the metacarpal head.
Aseptic necrosis of the head of the metacarpal is rare, and there
are only a few reports in the English-language literature7. This condition may be secondary
to trauma2,7 or steroid use5;
it may also be seen in patients with systemic lupus erythematosus
or in those who have had a renal transplantation8.
In addition, it has been reported to occur in association with Freiberg
disease4. Wright and Dell reported
on a patient who had aseptic necrosis of the metacarpal head with
later development of a similar problem on the contralateral side6.
The treatment of this condition has varied. Splinting, curettage,
bone-grafting, and joint arthroplasty9 have
all been advocated. Gauthier and Elbaz were the first authors, to
our knowledge, to report the successful treatment of Freiberg infarction
with a dorsiflexion osteotomy of the metatarsal head. They believed
that, by bringing the healthy plantar aspect of the metatarsal head
to articulate with the proximal phalanx, the joint mechanism could
be improved10. Good results with
this procedure were also reported by Kinnard and Lirette11.
These good clinical results following treatment of Freiberg disease
encouraged us to attempt this procedure for the treatment of avascular
necrosis of the head of the metacarpal. Theoretically, a volar flexion
osteotomy should reduce the range of extension. In our patient,
however, the range of motion improved in both flexion and extension,
apparently because of diminished pain.
If osteonecrosis of the metacarpal head is left untreated, collapse
of the head is likely to occur, perhaps leading to painful degenerative
arthritis3-8. The procedure that
we have described is another method for treating this problem, provided
that the articular cartilage on the dorsal aspect of the metacarpal
head is healthy.
Note: The authors thank Jack F. Rocco, MD, Chairman of Orthopaedic
Surgery at Misawa Air Base, for his suggestions and advice during
this investigation.