Swelling Management After Knee Replacement

To determine if inelastic adjustable compression garment results in improved surgical limb swelling control (bioimpedance assessment - primary outcome) after TKA compared to control (TED hose).

Total knee arthroplasty (TKA) is commonly performed to address disability from end-stage osteoarthritis (OA) in older adults and is expected to increase five-fold by 2040 to 3.5 million TKAs annually. Although TKA is effective at reducing pain, it is a substantial acute trauma to the joint that exacerbates the underlying weakness and disability common with OA, leading to long-term atrophy and further disability. Attenuation of this acute loss of strength and function leads to improved long-term outcomes. Key to preventing this acute loss is effectively managing postoperative knee swelling.

Knee swelling after TKA is profound and is theorized to be a major driver of this acute strength and functional loss. The average level of swelling peaks at a 35% increase in the first week after surgery. During the initial postoperative period, quadriceps strength decreases by 60% leading to decreases in functional performance of up to 90%. This early postoperative strength loss is driven by a deficit in quadriceps activation which limits rehabilitation potential acutely and leads to long term losses of quadriceps strength up to 42%. Quadriceps weakness results in long-term decreases in gait speed, balance, stair-climbing ability, and chair rise ability. Early functional decline increases the risk for falls and disability later in life. Furthermore, postoperative knee swelling has also been associated with increased pain, decreased range of motion (ROM) and post-surgical complications, such as deep venous thrombosis (DVT) and infection. However, traditional postoperative interventions such as elastic compression stockings (thromboembolism-deterrent \[TED\] hose) have demonstrated minimal effectiveness in reducing swelling after TKA.

The investigators have demonstrated in a pilot cohort study (N=16) that an inelastic, adjustable compression garment was related to decreases in swelling by 50% in the early postoperative period. However, there is a need to more formally evaluate the effects of this garment in a more robust design as well as determine the preliminary effects of this garment on important downstream clinical outcomes (e.g., strength and function) prior to initiating a larger clinical trial.

Therefore, the investigators propose a randomized controlled study of 58 older adult participants undergoing TKA to determine if the utilization of an inelastic adjustable compression garment (INCOM) reduces postoperative swelling more than elastic TED hose (CONTROL). Both groups will wear the assigned garments for the first three weeks after TKA and participate in a standardized rehabilitation program after TKA. Outcomes will be assessed preoperatively and postoperatively at weeks 1,2, 3 (end of intervention), and 12.

AIM 1: To determine if INCOM results in improved surgical limb swelling control (bioimpedance assessment - primary outcome) after TKA compared to CONTROL.

Hypothesis 1: INCOM will demonstrate reduced surgical limb swelling compared to the CONTROL group at 1, 2, and 3 weeks (primary endpoint) after TKA, and group differences will persist at 12 weeks.

AIM 2: To explore the preliminary efficacy of INCOM on the outcomes of quadriceps strength (dynamometer), pain (numeric pain rating scale), ROM (goniometry), physical function (30-second Sit to Stand test, Timed Up and Go), and patient-reported outcomes (WOMAC) compared to CONTROL.

Hypothesis 2: Direction of the effect will favor the INCOM group for strength, pain, ROM, physical function, and patient-reported outcomes compared to the CONTROL group at weeks 1,2, 3 and 12 weeks after TKA.

Eligibility Criteria:
Inclusion Criteria:

* Primary, unilateral total knee arthroplasty (TKA)
* Age 50 years or older

Exclusion Criteria:

* Surgical complication necessitating an altered course of rehabilitation
* Unable to attend outpatient rehabilitation 2x/week for 3 weeks following surgery
* Inability to don/doff garment
* Neurological, cardiovascular, or unstable orthopedic conditions that limit function
* Medical conditions that cause chronic lower extremity swelling
* Contralateral TKA within past year
* Pain \>5/10 in their contralateral knee or definite plans on having their other knee replaced in the next year
* Current tobacco smoker
* Use of illegal drugs
* Uncontrolled diabetes (hemoglobin A1c level \>8.0)
* Body mass index \>40 kg/m2