Macroscopic comparison of open Metzenbaum and ultrasound-guided fasciotomy techniques for surgical treatment of the hindlimb proximal suspensory ligament desmopathy in horses: A cadaveric anatomical study.

OBJECTIVE

To macroscopically characterize and compare the open Metzenbaum (FOM) and ultrasound-guided (FUG) plantar fasciotomy techniques for decompression of the hindlimb proximal suspensory ligament (PSL), and to determine whether either approach induces intraligamentous splitting (ILS).

STUDY

DESIGN

Cadaveric experimental study.

SAMPLE POPULATION: Paired hindlimbs from 10 adult horses with no history of hindlimb lameness.

METHODS

Each horse contributed one limb to FOM and the contralateral to FUG. All procedures were performed by a single surgeon, and incision measurements were obtained by a blinded examiner. Skin, fascia, and ILS lengths were recorded after dissection. Integrity of the deep branch of the lateral plantar nerve (DBLPN) was evaluated macroscopically. Paired t-tests compared FOM and FUG values (p < .05).

RESULTS

Both techniques induced PSL ILS. Mean ± SD incision lengths (cm) for FOM versus FUG were: skin 5.02 ± 0.41 versus 1.28 ± 0.18; fascia 5.54 ± 0.44 versus 4.39 ± 0.22; and ILS 5.33 ± 0.42 versus 4.37 ± 0.24. The FUG technique produced 74% shorter skin, 21% shorter fasciotomy, and 18% shorter ILS incisions compared to FOM (all p < .0001). No macroscopic evidence of DBLPN injury was observed.

CONCLUSION

Both FOM and FUG plantar fasciotomy techniques produced ILS while achieving PSL decompression. FUG required smaller incisions, confirming comparable anatomical efficacy with reduced invasiveness.

CLINICAL RELEVANCE: Intraligamentous splitting appears unavoidable during plantar fasciotomy, but the FUG technique limits its extent and associated soft-tissue disruption, supporting its use as a safer, less invasive alternative in clinical cases of chronic PSL desmopathy.