Primary End-to-End Repair of Subacute Extensor Hallucis Longus Tendon Rupture Supported by a Preserved Extensor...

Area of Science:

• Orthopedic Surgery
• Anatomy
• Sports Medicine

Background:

• Extensor hallucis longus (EHL) tendon rupture is uncommon, often requiring complex reconstruction in the subacute phase due to tendon retraction.
• Anatomical variations, like the extensor hallucis capsularis (EHC), are rarely reported for their influence on EHL rupture repair.
• Subacute EHL ruptures typically present challenges for primary end-to-end repair, necessitating tendon transfers or grafts.

Purpose of the Study:

• To report a rare case of subacute EHL rupture successfully treated with primary repair.
• To highlight the surgical and anatomical significance of the extensor hallucis capsularis (EHC) in facilitating delayed primary repair.
• To emphasize the Olewnik Type IIb EHC variant's role in maintaining tendon alignment.

Main Methods:

• Case report of a 26-year-old female with a subacute EHL rupture 1 week post-laceration.
• Diagnosis confirmed via MRI, followed by surgical exploration 11 days post-injury.
• Identification of an Olewnik Type IIb EHC variant and performance of a six-strand Yoshizu Type I repair.

Main Results:

• The identified EHC variant prevented significant proximal tendon retraction, leaving only a 5-mm gap.
• Primary end-to-end repair was successfully achieved due to the EHC's stabilizing effect.
• The patient achieved full strength and motion by 12 weeks post-rehabilitation without complications.

Conclusions:

• Preservation of the EHC can maintain partial extensor mechanism continuity, enabling primary repair in select subacute EHL ruptures.
• Awareness of the EHC, particularly the Olewnik Type IIb variant, is crucial for surgical planning and decision-making in EHL injuries.
• This case expands the potential indications for primary repair in subacute EHL tendon ruptures.