Perianchor Cyst Formation, Tendon Healing, and Clinical Outcomes Following Arthroscopic Rotator Cuff Repair

Perianchor cyst formation is a commonly observed finding on MRI after arthroscopic rotator cuff repair, but its clinical significance is still unclear. These cysts may be related to mechanical factors such as stress distribution around the anchor, micromotion at the bone-anchor interface, and local bone quality.

Different anchor materials (soft, PEEK, and metal) may behave differently in terms of load transfer and biological response. In addition, surgical factors such as the number of anchors used, their insertion angle, and the repair technique (single-row vs. double-row) may influence the formation and size of peri-anchor cysts. However, the combined effects of these variables have not been clearly defined.

Another important question is whether they reflect impaired tendon healing. Their relationship with tendon integrity, commonly evaluated using the Sugaya classification, remains uncertain. Similarly, it is not clear whether cyst characteristics are associated with clinical outcomes such as pain, shoulder function, and range of motion.

This prospective cohort study aims to evaluate the relationship between anchor-related parameters and perianchor cyst formation in a systematic way. The study will specifically analyze how anchor type, number, insertion angle, and repair configuration affect cyst volume and pericystic fluid accumulation.

In addition, the study will investigate whether peri-anchor cysts are associated with tendon healing and clinical outcomes. MRI findings will be correlated with validated clinical scores (ASES, Constant-Murley, VAS) and range of motion measurements.

A multivariable statistical model will be used to assess both independent and combined (interaction) effects of surgical variables. The potential of peri-anchor cysts as a predictive imaging biomarker for tendon healing and clinical outcomes will also be evaluated.

Overall, this study aims to better understand the clinical importance of peri-anchor cysts and to provide guidance for optimizing anchor selection and surgical technique in rotator cuff repair.

• MRI (Diagnostic test), also known as Magnetic Resonance Imaging: Measure of Perianchor Cyst Formation using 3D Slicer Image Computing Platform

Primary outcomes

• Perianchor Cyst Volume [Up to 12 months]: To determine the effect of anchor-related surgical parameters on peri-anchor cyst volume.
• Deadman's Angle [Up to 12 months]: Relation between anchors angle and cyst volume

Secondary outcomes

• Tendon Healing Classification with using Sugaya Classification [12 months after surgery.]: Type I (sufficient thickness with homogeneous low intensity), Type II (sufficient thickness with partial high-intensity area), Type III (insufficient thickness without discontinuity), Type IV (minor discontinuity indicating a small retear), and Type V (major discontinuity indicating a medium or large retear). Types I-III are generally considered indicative of an intact repair, whereas Types IV and V represent retears.
• Range of Motion [Preoperatively and 6, and 12 months after surgery.]: flextion, abduction, internat rotation, external rotation
• American Shoulder and Elbow Surgeons (ASES) Score [Preoperatively and 6, and 12 months after surgery.]: The American Shoulder and Elbow Surgeons (ASES) Score will be used to assess shoulder pain and functional status. The ASES is a validated, patient-reported outcome measure consisting of a pain visual analog scale (VAS) and 10 questions evaluating activities of daily living. Scores range from 0 to 100, with higher scores indicating better shoulder function and less pain.
• Constant-Murley Score (CMS) [Preoperatively and 6, and 12 months after surgery.]: The Constant-Murley Score (CMS) will be used to evaluate overall shoulder function. The CMS is a validated composite outcome measure that assesses pain, activities of daily living, range of motion, and shoulder strength. Total scores range from 0 to 100, with higher scores indicating better shoulder function.
• Oxford Shoulder Score (OSS) [Preoperatively and 6, and 12 months after surgery.]: The Oxford Shoulder Score (OSS) will be used to assess patient-reported shoulder pain and function. The OSS consists of 12 questions related to pain and activities of daily living experienced over the previous four weeks. Total scores range from 0 to 48, with higher scores indicating better shoulder function and lower levels of pain.

Sex: All, ages: 18 Years to 70 Years

Inclusion Criteria:

* Age 18-70 years
* Undergoing primary arthoroscopic rotator cuff repair
* Availability for MRI follow-up
* Ability to provide informed constent

Exclusion Criteria:

* Previous shoulder surgery
* Active infection
* Inflammatory joint disease
* Acute traumatic massive tears
* Inability to complete follow-up

• Ro K, Pancholi S, Son HS, Rhee YG. Perianchor Cyst Formation After Arthroscopic Rotator Cuff Repair Using All-Suture-Type, Bioabsorbable-Type, and PEEK-Type Anchors. Arthroscopy. 2019 Aug;35(8):2284-2292. doi: 10.1016/j.arthro.2019.03.032. Epub 2019 Jul 23. PMID 31350085
• Strauss E, Frank D, Kubiak E, Kummer F, Rokito A. The effect of the angle of suture anchor insertion on fixation failure at the tendon-suture interface after rotator cuff repair: deadman's angle revisited. Arthroscopy. 2009 Jun;25(6):597-602. doi: 10.1016/j.arthro.2008.12.021. Epub 2009 Mar 17. PMID 19501288

• ONUR GULTEKIN, MD, Principal investigator, FATIH SULTAN MEHMET RESEARCH AND TRANING HOSPITAL