432 Dionysian and Eaton / Outcome of Volar Plate Arthroplasty of Finger
averaging only 40° of active motion (Table 1,
patients 13 and 16). The interval between injury
and surgery, however, was quite prolonged, aver-
aging 29 weeks. Overall the final motion appeared
less favorable for older patients; however, because
of the small patient sample, this was not statisti-
cally significant. No significant difference was
noted in grip strength from side to side. At the
follow-up examination most patients had a resid-
ual increase in the PIP joint circumference (aver-
age, 3 mm or 5%) but were not symptomatic.
Radiographic evaluation showed that all joints
were reduced and there was an essentially congruous
relationship between the proximal phalangeal con-
dyles and the middle phalanx. This was best ob-
served on lateral projections. Although it is difficult
to absolutely quantify, in 10 patients the defect in the
volar lip of the base of the middle phalanx appeared
to have reconstituted as much as 80%. This finding
was particularly noted in comparison between the
lateral projections of the immediate postoperative
and late follow-up radiographs. The volar bony de-
fect, which was the site of the debrided volar plate
avulsion fragments, had reconstituted with metaph-
yseal bone. In 4 patients it appeared to be completely
remodeled in the lateral x-ray, resembling the adja-
cent noninjured middle phalanx (Fig. 1) (Table 1).
Despite the frequent intraoperative observation of a
dorsal proximal condylar cartilage defect at the time
of surgery, there was no radiographic evidence of
this as a late dorsal joint narrowing.
Four patients, who had an average follow-up pe-
riod of 13 years, showed radiographic evidence of
early joint narrowing. The patient with the longest
follow-up period (26 years) showed a congruous but
slightly narrowed joint space, yet had a pain-free
active ROM of 110° (Table 1, patient 4) (Fig. 2).
Three patients had slight irregularities of the middle
phalanx contour and demonstrated an average total
PIP active ROM of 47°. Of those who had a fol-
low-up period of longer than 10 years, only 2 showed
joint irregularities: a 59-year-old woman who had a
10-month delay of surgery and the patient with the
26-year follow-up period. Both patients were free of
pain.
bly related to extensor tendon-periosteum adhesions
or oblique retinacular ligament tightness secondary
to mild volar migration of the lateral bands following
operative stretching of the dorsal extensor mecha-
nism. Restriction of PIP joint motion was more com-
mon in the patients with delayed surgeries. None of
the patients with residual flexion contractures was
interested in joint release. One patient had a bouton-
niere deformity when examined several years after
surgery. She had moved from the area 5 weeks after
surgery and was unable to recall when this deformity
had developed. All but this latter patient were com-
pletely satisfied with their surgical results.
Angular PIP deformities were noted in 2 patients
with more than 10° of ulnar or radial deviation.
These patients had greater than 20° angular deformi-
ties before surgery that could not be completely
corrected at the time of surgery. Ulnar deviation
predominated, 1 patient having 30°, 1 patient with
20°, and another patient 10°. Two patients had sub-
sequent corrective osteotomies without noteworthy
loss of PIP motion.
Case Report
A 39-year-old social worker sustained an unstable
fracture-dislocation of the right fifth PIP joint while
playing basketball (Fig. 1A). Surgery was performed
6 days later. At the 18-year follow-up examination
(Fig. 1B) he was found to have 0°/95° active motion
of the PIP and full DIP motion and symmetrical grip
strength. He reported no pain at rest, with any activ-
ity, or with weather changes.
Discussion
Irregular articular surfaces, particularly if they are
also incongruous, are considered to carry a strong
potential for accelerated cartilage attrition and pre-
mature degenerative arthritis. The PIP joint, how-
ever, is anatomically unique, permitting resurfacing
of the deformed cartilage by advancement of a local
vascularized fibrocartilage pedicle, the volar plate. A
smooth, reasonably congruous articular surface may
be anticipated, since as the fibrocartilaginous pedicle
is advanced distally, it is molded around the curva-
ture of the proximal phalangeal condyle, assuming
its contour. In over 90% of the early surgical patients
(Ͻ4 weeks to surgery), the crushed, impacted sub-
chondral bone of the middle phalanx underwent sig-
nificant remodeling with at least partial reformation
of the volar lip (Table 1) (Fig. 1).
Complications
There were no infections, pin track problems, or
neurovascular complications. There were no early or
late PIP dislocations. Some degree of restriction of
DIP flexion was noted in half of the patients, possi-