Clinical trial NCT03909178: Arthroscopic Labral Repair Versus Physical Therapy for Tears of the Acetabular Labrum
Official title: Arthroscopic Labral Repair Versus Physical Therapy for Tears of the Acetabular Labrum in Patients Age 40 and Older
Study type: INTERVENTIONAL
Overall status: ACTIVE_NOT_RECRUITING
Phase: NA
Conditions: Acetabular Labrum Tear
Femoro Acetabular Impingement
Hip Arthroscopy
Physical Therapy
Osteoarthritis, Hip
Keywords: Acetabular Labrum Tear
Femoro Acetabular Impingement
Osteoarthritis
Hip Arthroscopy
Prospective
PROMs
mHHS
HOS
NAHS
LEFS
iHOT-33
RCT, Randomized Control Trial
Physical Therapy, PT
Osteoarthritis, Hip
Tonnis
Outerbridge
Older than 40 years old
Lead sponsor: Massachusetts General Hospital
Sponsor class: OTHER
First posted: 2019-04-09
Enrollment: 110
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: Tears of the acetabular labrum appear to be common with the prevalence of asymptomatic tears in the general population approaching 66% and 70% based on cadaveric dissection and magnetic resonance imaging, respectively. Despite this prevalence, there is no currently accepted justification for performing labral repair in an asymptomatic patient despite the many postulated biomechanical benefits that an intact labrum imparts to the hip joint.

Representing a smaller proportion of all tears, symptomatic tears of the acetabular labrum present a therapeutic challenge. Current treatment modalities range from conservative measures to open surgical intervention. Conservative measures have typically included: activity modification, the use of non-steroidal anti-inflammatory drugs (NSAIDs), physical therapy (PT), core strengthening and improvement of sensory motor control. In the past two decades, technological advances in the form of surgical instrumentation and traction devices have facilitated less invasive arthroscopic techniques to diagnose and treat hip problems and as such is now the preferred treatment modality for many orthopedic surgeons treating patients with hip pathology.

Determining which patients, using age and arthritic burden as predictors, can benefit from labral repair is paramount for several reasons. Showing arthroscopic repair is of little or no benefit to a specific cohort can reduce the number of unnecessary surgeries performed, increase the use of conservative therapy (if validated) and reduce the interval between diagnosis and total hip replacement.

Detailed description: There has been only one prospective study documenting the outcomes of patients treated with physical therapy for intra-articular conditions of the hip. These conditions included mild FAI and mild developmental dysplasia of the hip. Here, physical therapy was given as a first line treatment. Those who did not make satisfactory improvements in pain or wished to have surgery were then scheduled for surgery to repair the defects. Patients saw improvement in validated outcome measures at one year.

Although there have been studies looking at age secondarily in patients with labral tears, there is no prospective evidence to endorse or refute a recommendation of hip arthroscopy for patients of any age being treated for a tear of the acetabular labrum.

Most recently, the authors involved in this study performed a retrospective investigation (unpublished data) to capture patients with clinically and radiographically confirmed acetabular labral pathology electing to undergo conservative management defined as the refusal of surgical intervention. Based on a retrospective review of 894 patients presenting to clinic over a 10-year period, the investigators identified 22 patients with labral pathology that were treated non-operatively. Retrospective case control analysis was performed using outcome questionnaires administered to both surgical and non-surgical cohorts. The investigators found that patients with labral tears managed non-operatively appear to score highly on hip function outcome scores, preliminarily indicating there may be some benefit in using conservative management alone in the treatment of labral pathology.

This is a 12-month prospective randomized control trial (RCT), which will enroll 121 subjects with evidence consistent with a tear of the acetabular labrum. Labral tear will be diagnosed by clinical exam and positive MRI findings. Subjects will receive conservative physical therapy treatment alone or arthroscopic surgical labral repair and physical therapy. The investigators anticipate that pain, range of motion, activity level, and functional performance, as judged by validated outcome measures and serial physical exams, will improve when compared to baseline. The investigators also anticipate that the level of response will be greater in the surgical treatment group than in the physical therapy group at 12 months.

Our Primary Outcome is change in the modified Harris Hip Score at 12 months. Secondary outcomes include changes in other outcomes measures (LEFS, HOS, NAHS, iHOT-33), patient satisfaction, degree of improvement on physical exam, longer-term functional outcomes (i.e., at 2, 5, and 10 years), and the influence of OA severity (Outerbridge scoring) and location on the aforementioned outcome measures.

Eligibility criteria: Inclusion Criteria:

1. Age 40 or greater: higher likelihood or undetectable OA on imaging
2. Symptoms consistent with a tear of the acetabular labrum (at least one: catching, clicking, popping, pain with sitting, episodic pain, pain with hip flexion, adduction, and/or internal rotation): asymptomatic labral tears do exist in the general population however there is not definitive evidence to suggest treatment of asymptomatic tears is beneficial.
3. Symptoms not due to some other acute process in or around the hip (including septic arthritis, osteonecrosis, hemarthrosis, iliotibial band syndrome, fractures of the femoral neck or head, fractures of the acetabulum, greater trochanteric pain syndrome, sacroiliac joint pain, piriformis syndrome, low back pain associated with hip pain and not knee nor acute low back injury): certain conditions are not treatable by either arthroscopy or physical therapy. Some of these conditions can be managed with physical therapy but not arthroscopy.
4. Availability of hip radiographs and MRI: needed to assess eligibility
5. Evidence on MRI of a tear of the acetabular labrum: documentation of acetabular labrum tear
6. Willingness to undergo randomization and ability to understand and sign informed consent document: ability to understand study and consent willingly

Exclusion Criteria:

1. Less than 2 mm of joint space on standing plain anterior-posterior radiographs of the hip: indicative of severe osteoarthritic disease and the patient would benefit more from a total hip replacement
2. Developmental dysplasia of the hip: distorted acetabular anatomy and biomechanics
3. Kellgren-Lawrence Grade 4 changes: classified as large osteophytes, marked narrowing of joint space, severe sclerosis, and definite deformity of bone contour; indicative of severe OA
4. Tonnis Grade 3 changes: classified as large cysts in the head or acetabulum, severe narrowing or obliteration of the joint space, severe deformity of the head, and necrosis; indicative of OA
5. Unexpected pathology at the time of arthroscopy: source of pain less likely to due dysfunction of the labrum and more likely due to aberrant extra-articular biology
6. Same site surgery: complex anatomy
7. Back pain greater than hip pain or back pain associated with leg symptoms below the knee: source of pain less likely to be originating from the hip and more likely to be referred from the back/spine
8. Back pain associated with positive neural tension signs e.g. positive slump test, positive SLR (straight leg raise), positive reflex changes or drop foot: source of pain less likely to be originating from the hip and more likely to be referred from the back/spine
9. Knee pain greater than hip pain: source of pain less likely to be originating from the hip and more likely to referred from the knee
10. Bilateral tears of the acetabular labrum: difficult to gauge patient progress after treatment
11. Contraindication to surgery or physical therapy: cannot tolerate either treatment grouping
12. Alternate form of PT for greater than 6 weeks: will negatively augment results. May affect recruitment.

Primary outcomes:
measure: Change in mHHS Surveys From Preoperative to Various Postoperative Timepoints
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
Secondary outcomes:
measure: Change HOS Surveys From Preoperative to Various Postoperative Timepoints
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
measure: Change NAHS Surveys From Preoperative to Various Postoperative Timepoints
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
measure: Change iHOT--33 Surveys From Preoperative to Various Postoperative Timepoints
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
measure: Change LEFS Surveys From Preoperative to Various Postoperative Timepoints
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
measure: Degree of Improvement on Hip VAS Pain Score
timeFrame: Baseline (pre-operative), 3 months, 6 months, 12 months
Other outcomes:
Locations:
city: Boston
country: United States
facility: MGH, Massachusetts General Hospital
state: Massachusetts
Study officials:
affiliation: Massachusetts General Hospital
name: Scott D Martin, MD
role: PRINCIPAL_INVESTIGATOR
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