Preliminary Clinical Outcomes Following Biologic Augmentation of Arthroscopic Rotator Cuff Repair Using Subacromial Bursa, Concentrated Bone Marrow Aspirate, and Platelet-Rich Plasma

Abstract

Purpose: To evaluate the clinical outcomes of patients who underwent arthroscopic rotator cuff repair augmented using subacromial bursa, concentrated bone marrow aspirate (cBMA), and platelet-rich plasma.

Methods: Sixteen patients were included in the study who underwent arthroscopic rotator cuff repair augmented using subacromial bursa, cBMA, and platelet-rich plasma from January 2018 to July 2018 and had a minimum 1-year follow-up. American Shoulder and Elbow Surgeons (ASES), Simple Shoulder Test, Constant-Murley, and Single Assessment Numerical Evaluation (SANE) scores were collected preoperatively and at terminal follow-up. To determine the clinical relevance of ASES scores, the minimal clinically important difference, substantial clinical benefit, and the patient acceptable symptomatic state thresholds were used. In vitro cellular proliferation of subacromial bursa (nucleated cells/gram) and cBMA (nucleated cells and colony-forming units/cc) samples was evaluated and correlated to clinical outcomes scores.

Results: Mean follow-up was 12.6 ± 1.8 months (range 12-19 months). Patients achieved significant improvement in ASES (45.8±22.5_pre vs 88.5 ± 14.6_post, Δ44.7 ± 20.7; P = .001), Simple Shoulder Test (4.3 ± 3.2_pre vs 10.4 ± 1.6_post, Δ5.7 ± 3.9, P = .002), Constant-Murley (44.3 ± 18.2_pre vs 83.6 ± 17.5_post, Δ37.2 ± 21.8; P = .001), SANE (13.3 ± 10.7_pre vs 86.3 ± 17.5_post, Δ71.9 ± 22.9; P = .001), and pain scores (5.0±2.8_pre vs 1.1 ± 1.6_post, Δ3.5±2.5, P = .001) at final follow-up. With regards to ASES score, 93.8% of patients achieved the minimal clinically important difference, 93.8% the substantial clinical benefit, and 62.5% reached or exceeded the patient acceptable symptomatic state criteria. There was a significant positive correlation of nucleated cell count of cBMA with postoperative SANE score (r = 0.707; P = .015) and delta in ASES score (r = 0.727; P = .011). All other correlations were found to be nonsignificant (P > .05, respectively).

Conclusions: Patients undergoing arthroscopic rotator cuff repair augmented using the Mega-Clot with bursa technique achieved significant improvement in functional outcomes at a minimum 1-year follow-up, with 93.8% of patients reaching substantial clinical benefit.

Level of evidence: Level IV, therapeutic case series.

Fig 1

Harvest and processing of PRP. At the beginning of surgery, 60 mL of venous peripheral whole blood are drawn (A) and then processed using a fully automated 3-sensor technology system based on flow cytometry and light absorption (B) to obtain approximately 3 mL of PRP (C). (PRP, platelet-rich plasma.)

Fig 2

Harvest and processing of BMA. BMA is obtained from the proximal humeral head during arthroscopic rotator cuff repair using a non-fenestrated trocar (A). The harvested BMA, consisting of blood, bone marrow, and arthroscopic fluid (B), is transferred to the Angel System (Arthrex, Naples, FL) (C) and concentrated using a 15% hematocrit setting (D). (BMA, bone marrow aspirate.)

Fig 3

Harvest and processing of subacromial bursal tissue. Subacromial bursa is obtained from over the rotator cuff tendon using a laparoscopic grasper device (A). The sample (B) is then chopped using sterile tenotomy scissors until becoming a finely minced, gooey particulate (C).

Fig 4

Delivery of the prepared clot during rotator cuff surgery in a right shoulder. The final clot, usually having a total size of 16 to 24 cc (A), is delivered to the repair site using the same non-fenestrated trocar that was used for bone marrow aspiration (B). Arthroscopic view of the delivered clot via the anterior portal (C).

Fig 5

The viability of reimplanted MSCs within the clot is assessed using a live/dead assay, with 90% of the cells within the clot being viable (green fluorescence) while only 10% are dead (red fluorescence). The morphology of the clot using scanning electron microscopy shows a scaffold rich in fibrous strands, which are formed from fibrinogen found in the ACP and can be seen entangling platelets, red blood cells, erythrocytes, and MSCs within the clot. (ACP, autologous conditioned plasma; MSCs, mesenchymal stem cells)

Fig 6

Flowchart of patients included in the study. (cBMA, concentrated bone marrow aspirate; PRP, platelet-rich plasma.)

Fig 7

Preoperative to postoperative improvement in shoulder function following biologically augmented rotator cuff repair. ∗Indicates statistical significance. (ASES, American Shoulder and Elbow Surgeons; CM, Constant-Murley; SANE, Single Assessment Numerical Evaluation; SST, Simple Shoulder Test.)

Fig 8

Percentage of patients meeting outcomes thresholds. (ASES, American Shoulder and Elbow Surgeons; MCID, minimal clinically-important difference; PASS, patient acceptable symptomatic state; SCB, substantial clinical benefit.)