This cadaveric biomechanical study tested whether Ho:YAG laser thermal capsulorrhaphy weakens the inferior glenohumeral ligament complex. 57 bone-ligament-bone specimens were tensioned to 10% strain, half were lased to 10% shortening, then all were loaded to failure. It asks whether laser-induced collagen shortening compromises the strength of the primary anterior shoulder stabilizer.
Thermal capsulorrhaphy became popular in the late 1990s as an arthroscopic alternative to open capsular shift for shoulder instability. This paper asked the foundational biomechanics question: does heating the capsule to shrink it weaken it? At time zero the answer was reassuring. Strength parameters were preserved and failure never propagated through the lased tissue.
The cautionary signal is in the strain data. Lased specimens stretched more, and nearly 40% of the shortening was lost to increased laxity at low loads. This mechanically previews the recurrent instability and capsular attenuation that later plagued thermal capsulorrhaphy clinically.
Remember the key limitation: this is a time-zero cadaveric model in shoulders aged 74 to 91. It says nothing about the biologic healing response, which is where the technique ultimately failed. Thermal capsulorrhaphy was largely abandoned after reports of capsular necrosis, axillary nerve injury, and high recurrence.
This cadaveric biomechanical study tested whether Ho:YAG laser thermal capsulorrhaphy weakens the inferior glenohumeral ligament complex. 57 bone-ligament-bone specimens were tensioned to 10% strain, half were lased to 10% shortening, then all were loaded to failure. It asks whether laser-induced collagen shortening compromises the strength of the primary anterior shoulder stabilizer.
Thermal capsulorrhaphy became popular in the late 1990s as an arthroscopic alternative to open capsular shift for shoulder instability. This paper asked the foundational biomechanics question: does heating the capsule to shrink it weaken it? At time zero the answer was reassuring. Strength parameters were preserved and failure never propagated through the lased tissue.
The cautionary signal is in the strain data. Lased specimens stretched more, and nearly 40% of the shortening was lost to increased laxity at low loads. This mechanically previews the recurrent instability and capsular attenuation that later plagued thermal capsulorrhaphy clinically.
Remember the key limitation: this is a time-zero cadaveric model in shoulders aged 74 to 91. It says nothing about the biologic healing response, which is where the technique ultimately failed. Thermal capsulorrhaphy was largely abandoned after reports of capsular necrosis, axillary nerve injury, and high recurrence.