Total shoulder arthroplasty using a subscapularis-sparing approach: a radiographic analysis

Area of Science:

• Orthopedic surgery
• Arthroplasty
• Shoulder reconstruction

Background:

• Traditional total shoulder arthroplasty (TSA) requires subscapularis tendon release, potentially causing functional deficits.
• A novel subscapularis-sparing TSA technique aims to preserve the tendon via the rotator interval for faster recovery.
• Early reports suggest potential issues with component malpositioning and osteophytes in the novel approach.

Purpose of the Study:

• To compare the incidence of humeral head malpositioning, incorrect sizing, and residual osteophytes after subscapularis-sparing TSA versus traditional TSA.
• To evaluate the anatomic restoration of the humeral head using postoperative radiographs.

Main Methods:

• Prospective randomized trial comparing traditional TSA with subscapularis-sparing TSA.
• Surgeons were blinded to randomization until surgery.
• Radiographic analysis included humeral head height, centering, medial offset, diameter (HHD), and head-neck angle by two independent reviewers.

Main Results:

• No significant differences in humeral head height, centering, medial offset, HHD, or head-neck angle between groups.
• Significantly more postoperative osteophytes were observed in the subscapularis-sparing TSA group (P = .0001).
• More outliers in HHD (mismatch >4 mm) were noted in the subscapularis-sparing TSA group.

Conclusions:

• Subscapularis-sparing TSA can achieve anatomic restoration of the shoulder.
• Concerns exist regarding retained osteophytes and humeral head diameter mismatch in the subscapularis-sparing technique.
• Long-term outcomes of subscapularis-sparing TSA require further investigation.