Overview
This is single center randomized controlled trial based on an alpha-adaptive design and a 1:1 allocation ratio. The study compares shoulder functional outcomes, complications, subscapularis muscle integrity and number of physical therapy (PT) visits between two different postoperative shoulder physical therapy protocols. The study will be conducted at an outpatient orthopaedic center affiliated with an inpatient surgery center. The diagnosis of rotator cuff arthropathy will be made by the orthopaedic surgeon and the decision to proceed with a reverse total shoulder arthroplasty will be determined by a consensus between the patient and surgeon. After the surgery, the patient will either follow the standard physical therapy protocol or the immediate accelerated protocol. Follow up visits will be performed at 2 weeks, 6 weeks, 3 months, 6 months, and 1 year after the surgery. Based on previous volume of reverse total shoulder arthroplasty in the preceding years, we expect the study to run for 3 years, with 2 years of recruitment and 1 year of follow-up.
Study Population
Inclusion Criteria
- 55 years of age.
- Candidate for a primary reverse total shoulder arthroplasty. (CPT code 23472)
- Capable of completing self-administered questionnaires.
- Be willing and able to return for all study-related follow-up procedures.
- Able and willing to give informed consent.
- Proficient in the English language.
Exclusion Criteria
In-Clinic
- Patients planning on undergoing a Primary Reverse Shoulder Total Arthroplasty due to proximal humeral fracture.
- Previous shoulder surgery including previous total shoulder arthroplasty or reverse total shoulder arthroplasty or hemiarthroplasty, or instability repairs
- Active bacterial infection of the shoulder.
- Any concomitant shoulder procedure.
- Additional ipsilateral or contralateral upper limb pathology that requires active treatment (i.e. surgery or brace).
- Peripheral vascular disease or other vascular disorders that would impair healing.
- Peripheral neuropathy or other neurological disorders that may impair the patient to ambulate.
- Patient is on workers compensation.
- Any condition requiring chemotherapy.
- Active tobacco user or former tobacco user who is not free of using tobacco for 8 weeks.
- Uncontrolled Diabetes Mellitus with an HbA1C > 7.5%.
- Current drug or alcohol abuse.
- Major medical illness (life expectancy less than 2 years or unacceptably high operative risk)
- Suspicion of cervical radiculopathy or myelopathy.
- Deltoid insufficiency on physical examination
Intra-operative:
- Iatrogenic glenoid fracture
- Post-operative:
- Neurological injury of the upper extremity.
- Complications from Primary Reverse Shoulder Total Arthroplasty (i.e. post-operative infection, bleeding, hardware failure).
Randomization
Patients will be randomly be assigned to the individual post-operative physical therapy group using a computerized random number generator. A block randomization scheme and an allocation ratio of 1:1 will be employed. The allocation sequence will be concealed in sealed envelopes and revealed after the surgery is performed. The randomization will be conducted by the manager of clinical research. Participants will be enrolled by a post-doctoral research fellow. The investigator will assign participants to the intervention and will be documented in the operative note and post-operative orders to make the physical therapists and nurses aware. The outcome assessor for range of motion and data analyst will be blinded after the intervention is assigned to the participant.
Interventions
Subjects in the immediate active shoulder rehabilitation group will be provided with a physical therapy home sheet. During their inpatient stay at the hospital post-operatively for 1-3 days, the physical therapist will teach and practice several stretching exercises with the subjects. The exercises include: elbow flexion/extension, forearm rotation, pendulum, wand external rotation, standing passive external rotation, supine assisted flexion range of motion (ROM), table slide flexion, scapular retraction, adduction, internal rotation, flexion, abduction with external rotation, external rotation on wall, and posterior capsular stretch. Upon discharge of the patient from the hospital, the physical therapist will specify the sets, repetitions, number of times per day and seconds to hold for each exercise. Additional outpatient physical therapy visits may be ordered if the patient has difficulty in performing the exercises or requests for it.
The patients in the standard group will follow what is the current standard of healthcare, which is a total of 18 outpatient physical therapy visits in a time span of 12 weeks. There will be 2 visits per week for the first 6 weeks followed by 1 visit per week for the next 6 weeks. The patient will be in a shoulder sling for 4-6 weeks and restricted from active range of motion (AROM) of the shoulder. During the first 6 weeks the patients will learn and practice the following exercises: passive range of motion of the shoulder in the scapular plane, active range of motion of the elbow, wrist, and hand, pendulum movements, scapular exercises (scapular retraction, depression, circles), and deltoid isometrics. In the last 6 weeks, the patient will begin active assisted range of motion and active range of motion of the shoulder, progress with the scapular and glenohumeral stabilization exercises. At week 10, exercises will progress from isometric to isotonic.
Outcomes
The primary outcome of this study is shoulder function measured by questionnaires and range of motion. Patient reported outcome measures used for this study is the American Shoulder and Elbow Score (ASES) and Simple Shoulder Test (SST) score. Range of motion will be measured with the help of a goniometer for forward elevation, external rotation and internal rotation. The measurements will be performed by a blinded orthopaedic surgeon fellow with at least 5 years of postgraduate clinical training experience. These will be collected at every visit: baseline, post-operative 2 weeks, 6 weeks, 3 months, 6 months, and 1 year. (Figure 1)
The secondary outcome is serial shoulder radiographs in the anteroposterior and lateral views to detect endoprosthesis loosening, scapular notching, and dislocation. Radiographs will be performed at every visit as well.
The tertiary outcome is a one-time shoulder ultrasound performed by a blinded musculoskeletal radiologist at the end of 1 year follow up to detect a tear of the subscapularis muscle.
The fourth outcome is number of outpatient physical therapy visits required for the shoulder.
Sample Size
The sample size calculation was based on the postoperative ASES score in a comparative study published by other authors.13 To detect a clinically relevant difference of 15.8 score between groups, with a mean improvement SD of 20.6, alpha of 5% and power of 80%, 31 patients were needed in each group. Assuming a drop-out rate of 20%, at least 37 patients were required per group. This leaves us with a total sample size of 74.
If we consider the minimal clinical important difference (MCID) of 3.0 for the Simple Shoulder Test score, we would need 19 patients per group, respectively to possibly reach statistical significance in these outcome scores. A total of 34 patients will be necessary to detect a 10°difference in range of motion of the shoulder in all planes based on an SD of 10°.
Recruitment
The participants will be recruited from an outpatient orthopaedic surgery clinic. If a participant tentatively meets the criteria for the study, the investigator will inform the research fellow/coordinator to complete the recruitment process. Patients who are willing to participate in the randomized trial will be asked to sign a Consent Form. Basic demographic data will be collected for both groups to assess independent variables (age, gender, BMI, hand dominance, race, ethnicity, type of osteoarthritis baseline shoulder function (American Shoulder and Elbow Society (ASES) score, SST score and PROMIS Global Health-10, and baseline shoulder range of motion..
Data Collection Methods
Data on outcomes will be collected on a hardcopy format and transferred to a data collection software, REDCap. Case report forms will be provided to the research coordinator and radiologist to document findings. Surveys on patient reported shoulder function and general health will be completed at each visit on paper as well.
Statistical Analysis
Differences in baseline characteristics (i.e., intrinsic and injury-related variables) between both intervention groups will be assessed using the Student’ s t test (parametric continuous data), the Mann-Whitney U test (nonparametric continuous data) or the chi-square test (categorical data). Unadjusted analysis by intention-to-treat will be performed to test the difference in primary and secondary outcomes between the intervention groups. Student’ s t test (parametric continuous data), the Mann-Whitney U test (nonparametric continuous data) or the chi-square analysis (categorical data) will be used. A p value < 0.05 (two-sided tests) will be taken as threshold of statistical significance.
Monitoring and Quality Assurance
The institutions Data and Safety Monitoring Board (DSMB) will review the progress of the study to assure the rights and safety of participants, confirm the study conduct follows the guidelines of good clinical practice, assure maintenance of required documents, verify adherence to the protocol, monitor the quality of data collected, and assure accurate reporting and documentation of all adverse events. Research auditing will occur independently from the investigators.
Adverse events will be collected and recorded on the appropriate case report until the patient participation is complete at the 1 year post-operative time point. Adverse events will be noted subjectively from the patient or objectively during the follow-up visits.
All research documentation will be labelled with a unique person number as an identifier and stripped of any potentially identifiable information. Data will be stored in password-protected computers and locked filing cabinets as required within the administering institution.
Ethics and Dissemination
IRB approval was obtained from the HealthPartners Institute on October 18, 2018. Protocol modifications, addition of staff personal and changes to the consent form will be presented to the IRB as an amendment. Consent will be obtained by the research fellow or coordinator.
The study received full internal funding through the HealthPartners Institute via competitive process throughout all medical and surgical departments of the institute. The final trial dataset will be under the access of the research fellow/coordinator and statistician. There is no plans of sharing the data set and statistical analysis reports to the public.
Our plan is to present the results of our study via publication and abstract presentation. We initially plan to submit our study protocol to the BMC Trials Journal as a manuscript after IRB approval and before we begin recruitment to showcase our study to prevent duplicate work by other centers and creating an opportunity for other shoulder surgeons to provide constructive criticism to improve the study. On completion of final data analysis, an abstract will be submitted to appropriate shoulder conference i.e. American Shoulder and Elbow Society. Following this, we will write up our results in the form of a manuscript for journal submission.