The proposed project is novel in its goal to establish a foundation for evidence-based rehabilitative nutrition guidelines to enhance perioperative patient care and improve post-operative rehabilitative outcomes specific to muscle health (muscle mass, strength, and function) and quality of life in elective orthopedic surgery patients undergoing total joint replacement procedures.

Study Aims. Specific aims and their respective approach for the proposed investigation were:

Aim 1: Characterize energy status and protein intake in total hip arthroplasty and total knee arthroplasty patients prior to surgery.

Approach. Following approval of investigation by the Hartford Hospital Institution Review Board, data collection involved the inclusion of a research information sheet and a 3-day food record with instructions for the respective patient to complete prior to surgery.

Aim 2: Evaluate association between energy status, positive or negative energy balance on standard outcome measures assessed throughout physical rehabilitation to determine whether energy status and protein intake at admission predicts objective and subjective rehabilitative outcome measures. Dietary assessments (3-day food record, protein screener) occurred at time points corresponding to physical rehabilitative assessments per approach for Aim 1.

Approach. Total Hip Replacement assessments will occur between Day 1 following surgery and Week 2 and 6 months post surgery . Outcome measures included Pain Visual Analog Scale, Hip Disability Osteoarthritis Outcome Score, Timed Up and Go Test, 30 second Sit to Stand Test, Passive Hip Range of Motion and Active Hip Range of Motion.

Total knee assessments were taken post surgery on between Day 1 and Week 2 and at 4 to 6 Weeks, and 7 to 12 Weeks following surgery. These included Pain Visual Analog Scale, Knee Injury and Osteoarthritis Outcome Score, Timed Up and Go test, 30-second Sit to Stand Test, Passive and Active Knee Range of Motion, and Knee Strength.

Aim 3: Validate a protein screener developed by our research team and designed to characterize protein intake and protein source was administered pre- and post-operatively.

For the latter, time points were established according to respective treatment guidelines for Total Hip and Total Knee replacement patients, respectively.

Clinical Significance: The clinical relevance of the proposed project is the eventual development of evidence-based rehabilitative nutrition practice guidelines for orthopedic patients. The scientific literature specific to the role of perioperative nutrition on rehabilitative outcomes in patients undergoing elective total joint procedures, total hip arthroplasty and total knee arthroplasty in particular, is limited.

Background and Study Rationale. Orthopedic procedures are commonly undergone to treat injuries and chronic conditions affecting the hip and knee. Primary arthroplasties represented 86% of the 1.9 million hip and knee arthroplasties performed in the United States from 2012-2019. Total hip and total knee replacement procedures are typical in older men and women and persistent muscle loss is a shared clinical presentation for young as well as older individuals undergoing elective orthopedic surgery procedures. Energy status energy status and protein intake, nutrition factors known to affect muscle mass and strength in orthopedic patients, has not been characterized prior to admission. Whether this aspect of nutritional status might predict recovery of muscle mass, strength, and function in the context of standard practice/post-operative rehabilitative treatment guidelines is not known.

Elective orthopedic surgery patients face major challenges in maintaining muscle mass and function during the perioperative period. Patients receiving protein or essential amino acid supplementation following total hip and total knee replacement, show improvements in protein balance, patient reported outcome measures, as well as muscle mass, strength, and function. Investigations of larger sample size and longer study duration where protein intake is adequately characterized prior to surgery are needed in these patient populations to further determine connections between routine protein intake and post-operative muscle specific outcomes. Perioperative nutrition screening and assessment measures specifically tailored to orthopedic patients that are attentive to energy status and protein intake are needed. The development and validation of the protein screener proposed in for this project is a unique approach to efficiently acquiring valuable perioperative dietary information. Including subjective, as well as functional, outcome measures may reveal associations between energy status and dietary protein intake pre-operatively and rehabilitative outcomes specific to muscle health to support routine assessment of these dietary factors as prognostic indicators for patient recovery following total hip and total arthroplasty. The proposed project is novel in its goal to establish a foundation for evidence-based rehabilitative nutrition guidelines to enhance perioperative patient care and improve post-operative rehabilitative outcomes specific to muscle health (i.e., strength and function) and quality of life in elective orthopedic surgery patients undergoing total joint replacement procedures.

Approach. Following approval of investigation by the Hartford Hospital Institution Review Board, data collection involved the inclusion of a research information sheet and a 3-day food record with instructions for the respective patient to complete prior to surgery. Recruitment was done in collaboration with the perioperative program staff. Eligible patients and a member of the research team met with patients to determine interest, review study requirements, and obtain written, informed consent for study enrollment. Dietary assessments (protein screener and 3-day food record) occurred before and after surgery per treatment guidelines for total hip and total knee replacement patients, respectively. The protein screener was designed to characterize protein intake and protein source and the respective 3-day food record for participants was used to validate patient responses on screener. Routine clinical assessments per treatment guidelines for respective patient populations were done.

Statistical Approach. Means and standard deviations were determined for outcome measures. Data was analyzed using a 3 factor (energy status, protein intake, and rehabilitative outcome measures) repeated measures over time analysis of variance. Post hoc tests were applied where statistical significance is noted; alpha-level was set at P< 0.05.

Inclusion Criteria:

• Body Mass Index (BMI) between 18.5-34.9 kg/m2; receiving elective total hip or knee arthroplasty due to osteoarthritis for first time

Exclusion Criteria:

• Patients with any non-orthopedic impairment that can impact lower extremity function or mobility, such as paralysis, stroke, multiple sclerosis, and spinal cord injury

Post-enrollment exclusion criteria (if applicable)

For Aim 2:

• Patients who do not attend post-operative physical therapy at one of the identified locations (please see section: Project Personnel)
• Patients who are non-compliant with their physical therapy prescription (missing four or more scheduled sessions).

Healthy adults aged 50-70 yrs undergoing first elective total joint arthroplasty for hip or knee.