Arthroscopic Superior Capsular Reconstruction With Fascia Lata Autograft - Survivorship of the Autograft Analysis

Arthroscopic Superior Capsular Reconstruction With Minimally Invasive Harvested Fascia Lata Autograft - Clinical Outcomes and Survivorship of the Autograft Analysis

An irreparable rotator cuff tear (IRCT) is a challenge, with a controversial definition and different treatment options. None of the latter are exempt of limitations and their survivorship is one of the concerns. In 2013, Mihata et al. proposed a novel treatment option: arthroscopic superior capsular reconstruction using a fascia lata autograft (FL-ASCR) harvested through an open approach. Although no harvest site dysfunction was reported, concerns about donor site morbidity discouraged the use of this type of graft. In 2015, the investigators modified the original FL-ASCR introducing a minimally invasive fascia lata harvesting technique, aiming to reproduce FL-ASCR's promising clinical results in IRCT, while reducing donor site morbidity.

The investigators aim to: 1) Evaluate the mid-term outcomes and donor site morbidity impact of FL-ASCR with minimally invasive harvesting; 2) Analyze the mid-term graft integrity to determine its survivorship 3) Establish clinical and imaging graft integrity correlations to guide the future treatment algorithm.

Task 1 - Prospective evaluation of:

1. The mid-term shoulder outcomes of ASCR with minimally invasive harvested fascia lata autograft The objective of this task is to establish the 3 years postoperative clinical and radiological shoulder outcomes of FL-ASCR with minimally invasive harvesting. The secondary purpose of this task is to test if the FL-ASCR outcomes remain constant after the 2-year evaluation.

   Therefore, the FL-ASCR patients included in this study will have completed the preoperative, 6-month and 2-year postoperative evaluations and will undergo a 3-year postoperative evaluation of:

   1. Bilateral shoulder active range of motion (ROM): elevation, abduction and external rotation (with the arm at the side), measured in degrees with the use of an analogic goniometer; and internal rotation, defined as the highest vertebral body that the patient's thumb can reach, converted afterwards to a scale of 1-5 points: lateral thigh=0; buttock=1; sacrum=2; lumbar=3; 12th thoracic vertebra=4; 7th thoracic vertebra=5.);
   2. Bilateral shoulder strength (supraspinatus, infraspinatus, subscapularis and teres minor) measured in kilograms with the use of a digital dynamometer;
   3. Bilateral functional shoulder scores: the simple shoulder test (SST, 1-12 points), the subjective shoulder value (SSV, 0-100%) and the constant score (CS, 1-100 points).
   4. True anteroposterior shoulder view radiograph of the affected shoulder: the acromiohumeral interval (AHI), considering the distance between the top of the humeral head and the undersurface of the acromion, measured using a software measurement tool (PACS, Agfa HealthCare); the RCT arthritis will be graded according to the Hamada revised radiographic classification.

2. The donor site morbidity impact of FL-ASCR with minimally invasive harvesting The objective of this task is to establish the 3-year donor site morbidity subjective impact of FL-ASCR with minimally invasive harvesting. The secondary aim of this task is to test our hypothesis that the subjective impact of the donor site morbidity after FL-ASCR does not change significantly from the 2-year to the 3-year evaluation. Therefore, at the 3-year evaluation, the patients will be required to answer to the same three closed-ended questions that were asked at the 2-year evaluation to assess the donor site morbidity's impact on the patient's overall satisfaction of the surgical procedure: "Does the harvested thigh bother you?", "Does your shoulder surgery's end result compensate for your thigh's changes?", "Would you undergo the same surgery again?". Accordingly, the patients will also be asked asked, in a closed-ended questionnaire, if they noticed any of the following donor site changes: deformity, pain, numbness and specific donor site-related claudication.

Task 2 - Analysis of the mid-term graft integrity on the 3-year postoperative magnetic resonance imaging (MRI) to determine the graft mid-term survivorship

The objective of this task is to determine the 3-year postoperative survivorship of the graft, establishing the fascia lata superior capsular graft tearing rate and the most frequent site of graft failure at 3 years. A 1.5 Tesla MRI scanner (Siemens Magnetom, U.S.A.) will be used to acquire images in the coronal [proton density fat-saturated (PD FAT-SAT) and T1-weighted], sagittal (PD FAT-SAT and T2 FAT-SAT) and axial (T2* and PD) planes. We and, after blinding, two other independent experienced musculoskeletal radiologists will assess the MRI-images from each patient, in order to:

1. Identify any discontinuity of the graft which, if present, will be classified according to its site as a proximal, an intermediate or a distal tear; and as an anterior or a posterior tear.
2. Identify any discontinuity of the onlay repair of the rotator cuff remnants, which, if present, will be classified a tear of the onlay repair.
3. Grade the supraspinatus, infraspinatus, teres minor and subscapularis muscle fatty degeneration according to the Goutallier et al. classification.
4. Grade the RCT tendon remnants retraction in the coronal plane according to the Patte classification.
5. Grade the supraspinatus muscle atrophy according to the Thomazeau et al. classification.
6. Grade the supraspinatus muscle atrophy according to the tangent sign. The graft survivorship according to the three separate evaluations will be compared to establish the inter-observer reliability of the MRI graft survivorship results.

The type of progression of graft integrity will be determined by comparing the 6-month with the 3-year MRI evaluation of the graft survivorship.

Task 3 - Comparative analysis of the clinical, radiological and MRI preoperative and postoperative variables

The objective of this task is to find correlations between the graft survivorship and the results from tasks 1 and 2. The aim is to establish the clinical importance of mid-term graft survivorship.

The investigators will compare the ROM, shoulder strength, SSV, SST, CS and AHI from preoperative to 3 years postoperative; and from 2 years postoperative to 3 years postoperative (paired-samples t-test). The investigators will compare all continuous variables between the group of ASCR patients who underwent an additional onlay partial RCT repair and the group that underwent ASCR without an onlay partial RCT repair, between the anterior acromioplasty-ASCR group and the group that did not undergo an anterior acromioplasty, between the tenotomy-ASCR group and the no-LHBT group, between the preoperative and postoperative AHI<7mm group and the AHI≥7mm group, and between the intact-graft group and the graft-tear group (Mann-Whitney U test). The investigators will compare all categorical variables, including the donor site morbidity and overall subjective outcome results, between the groups (Fisher's exact test).

To determine the repercussion of FL-ASCR and of the graft integrity on the rotator cuff muscle function the investigators will compare the progression of the Goutallier classification of each rotator cuff muscle from preoperative to 3 years postoperative, as well as the cumulative Goutallier score (the sum of the fatty infiltration stages of the four muscles) and the global fatty muscle degeneration index (the mean value of the grades for the supraspinatus, infraspinatus, and subscapularis), between the intact-graft group and the graft-tear group.

A significant difference will be defined as P<0.05.

Inclusion Criteria:

• FL-ASCR by the same surgeon (principal investigator) since 2015
• completed the preoperative and the 6 months postoperative clinical, radiological and MRI assessments

Exclusion Criteria:

• secondary surgery for the removal of the implanted autograft in the shoulder which had previously ungergone the FL-ASCR procedure
• secondary surgery to the harvested thigh