Spontaneous index finger extensor tendon rupture in a SNAC wrist

Area of Science:

• Orthopedic Surgery
• Hand Surgery
• Musculoskeletal Research

Background:

• Spontaneous rupture of extensor digitorum communis and extensor indices proprius tendons is uncommon.
• These ruptures can be associated with dorsal carpus osteophytes, particularly in patients with a history of scaphoid fracture non-union and scaphoid non-union advanced collapse (SNAC) wrist.
• Correcting the underlying cause is crucial to prevent recurrent tendon issues.

Purpose of the Study:

• To report two rare cases of spontaneous index finger extensor tendon rupture.
• To describe a novel surgical treatment combining 3-corner arthrodesis with tendon interposition and transfer.
• To evaluate the outcomes of this surgical technique.

Main Methods:

• Surgical treatment involved 3-corner arthrodesis for SNAC wrist.
• Ruptured tendon fragments were interposed and reinforced with a supernumerary extensor digitorum communis tendon transfer.
• Suturing techniques included Pulvertaft weave and end-to-end anastomosis.

Main Results:

• Patients showed significant improvement in hand strength post-surgery.
• A slight decrease in range of motion and functionality was noted but did not impede daily activities.
• Isolated index finger extension was restored within 6 months postoperatively.
• No previous reports exist for this specific type of complication and surgical treatment.

Conclusions:

• 3-corner arthrodesis combined with tendon interposition and transfer offers a viable solution for spontaneous extensor tendon ruptures secondary to carpal osteophytes.
• This surgical approach can restore index finger function and strength while addressing the underlying wrist pathology.
• Further research is warranted to confirm the long-term efficacy of this technique in managing rare tendon ruptures.