Thumb CMC OA is common, with radiographic prevalence ranging from 7% to 35% in the
literature, with symptomatic OA affecting 2% to 6% of the population. There is
predilection for involvement of the non-dominant hand, and thumb CMC OA is the leading
cause of hand pain due to degenerative changes. Gender-specific differences in thumb CMC
OA prevalence have also been described in the literature. Retrospective review of 615
patients revealed a 6-fold higher prevalence of thumb basilar joint OA for females in
nearly every age group, noting the presence of radiographic OA at younger ages in
females, and quicker progression to end-stage degenerative changes.
While conservative treatment, such as injections, therapy, splinting, and
pharmacotherapy, may palliate symptoms, operative intervention is recommended if symptoms
are persistent. Trapeziectomy with or without suspensionplasty is most commonly performed
for advanced osteoarthritis, and studies have shown that trapeziectomy with ligament
reconstruction and tendon interposition (LRTI) is the most frequently performed
procedure. Because of the extensive nature of this surgery with dissection and removal of
the trapezium as a common central procedure, immobilization of the thumb and wrist has
been a standard part of postoperative protocols to improve postoperative pain, function,
and aid with return to daily activities.
Across many studies of operative technique and post-surgical care, there is no high-level
evidence on the optimal duration of postoperative immobilization. With no consensus on
the duration during which patients should restrict range of motion after thumb CMC joint
surgery, there is a gap in knowledge on this topic. Immobilization following surgery is
critical for wound healing, pain control, and aid with activities of daily living in the
early recovery period, though the duration of this must be weighed against the negative
impacts of immobilization, such as stiffness, contracture, and delay in return to full
function. The information gained in this study may allow hand surgeons to use an
evidence-based postoperative rehabilitation protocol. Thus, our goal is to compare
varying durations of postoperative immobilization after thumb CMC arthroplasty in a
randomized trial design.
In this study, we will prospectively evaluate varied duration of postoperative
immobilization in patients older than 40 years, undergoing base of thumb arthroplasty at
an academic, tertiary referral center. Patients will be randomized to either 2 or 6 weeks
of immediate postoperative immobilization in a plaster thumb spica splint or cast.
Functional outcome measures, including quickDASH (Disabilities of Arm, Shoulder, and
Hand), PROMIS UE (Patient Reported Outcome Measures Information System Upper Extremity)
form, and VAS (Visual Analog Scale) pain scale will be captured at short-term,
intermediate-term, and final follow-up periods. Additionally, exploratory objective
metrics, such as strength, range of motion (ROM), return to work, and occupational
therapy (OT) utilization will be monitored at all time periods.
Randomization into two cohorts of postoperative rehabilitation will occur via sealed
envelope at the time of surgery. Patients will be consented through a formal written
process detailing the purpose, risks, and benefits. Randomization will occur in a 1:1
ratio into 2-week versus 6-week immobilization groups. Opaque envelopes will be sealed
and only opened at the time of randomization, immediately after completion of the
surgical procedure, in the post-anesthesia care unit (PACU). Every patient will be
immobilized postoperatively in a nonremovable thumb spica plaster splint to allow for
swelling. At the 2 week (+/- 3 days) postoperative visit, patients will be placed into
either a cast for 4 additional weeks of immobilization (6-week immobilization group) or
be provided a removable thermoplastic thumb spica splint (2-week immobilization group)
and specifically instructed to use it for comfort "as needed" with removal at their
discretion. A similarly fashioned thermoplastic thumb spica splint will be provided to
the 6-week group after the duration of their immobilization, again with instructions for
"as needed" use. At the conclusion of each group's respective immobilization period, the
same standardized hand therapy rehabilitation regimen will be initiated.
