Compressive damage to the deep branch of the lateral plantar nerve associated with lameness caused by proximal suspensory desmitis.
ABSTRACT To describe pathologic changes in the deep branch of the lateral plantar nerve (DBLPN) of horses determined to be lame because of proximal suspensory desmitis (PSD), and to report the outcome after treatment by excision of a segment of the horses' DBLPN.
Retrospective case series.
Adult horses (n=16).
Horses determined to be lame on one or both pelvic limbs because of PSD were treated by excision of a segment of the DBLPN, and 30 nerves were examined histologically. Owners were contacted to obtain information about the horses >or=6 months after surgery.
Histologic changes suggestive of chronic nerve compression were identified in both nerves of 11 bilaterally lame horses and in the lame limb of 5 unilaterally lame horses. The nerve of the sound limb of 2 of 3 unilaterally lame horses that had bilateral nerve resection also had histologic changes compatible with nerve compression. Ten of 16 horses (62.5%) with follow-up information returned to soundness after excision of the DBLPN.
Pathologic changes of the DBLPN associated with compression may complicate PSD of the pelvic limbs. Excision of the nerve may resolve lameness caused by PSD.
Horses lame because of PSD of the pelvic limb may remain lame after desmitis has resolved because of compression of the DBLPN. Excising a portion of this nerve may resolve lameness.
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ABSTRACT: Desmopathies of the suspensory ligament are relatively frequent and vary in prevalence over different anatomical regions. This variation may be because of regional differences in tissue characteristics. To characterise different regions of healthy forelimb suspensory ligaments (SLs) by means of biochemical, biomechanical and histomorphological techniques. There is substantial topographical heterogeneity in the SL with respect to structural, compositional and functional characteristics. SLs were harvested from 38 limbs and used for biochemical (n = 20), biomechanical (n = 14) and histomorphological (n = 4) evaluation. Sulphated glycosaminoglycan (S-GAG), DNA and collagen content, degree of lysyl hydroxylation and numbers of enzymatic and nonenzymatic cross-links were determined in 7 regions of the SL: lateral and medial part of the origin (OM, OL), mid-body (MB), axial and abaxial parts of the lateral and medial branches (ILAX, ILAB, IMAX and IMAB, respectively). Passive resistance to tensile loading was measured in 5 regions of the SL (all except OL and OM). DNA content was lower in OL and OM than in all other parts. GAG content was also lower in OL and OM and highest in ILAB and IMAB. Collagen content was lower in OL/OM and highest in ILAX/IMAX. Pentosidine levels were highest in OL and significantly lower in the lateral insertion (ILAX/ILAB). There were no differences in hydroxylysylpyridinoline (HP) cross-links or lysyl hydroxylation. Stiffness (P<0.01) and modulus of elasticity (P<0.01) were substantially higher in the MB region than in all other regions except for IMAB. Strain at failure was lower in the MB region (P<0.0001), resulting in a comparable force at rupture as in the other regions. Matrix composition differs to a relatively limited extent between different regions of the SL. The mid-body of the ligament is stiffer than the branches, which have similar properties and relevance and mechanical differences between mid-body and branches/origin may explain some use-related differences in the prevalence of lesions.Equine Veterinary Journal 10/2010; 42(7):611-20. · 2.29 Impact Factor
- Equine Veterinary Education. 05/2010; 22(6):271 - 274.
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ABSTRACT: Neurectomy of the deep branch of the lateral plantar nerve and plantar fasciotomy have become accepted as methods of treatment of proximal suspensory desmopathy (PSD), but there are limited long-term studies documenting the outcome. To describe long-term follow-up in horses with PSD alone or with other injuries contributing to lameness and poor performance, including complications, following neurectomy and fasciotomy. Follow-up information was acquired for 155 horses that had undergone neurectomy and fasciotomy for treatment of PSD between 2003 and 2008. Success was classified as a horse having been in full work for >1 year post operatively. Horses were divided into 3 groups on the basis of the results of clinical assessment and diagnostic analgesia. Horses in Group 1 had primary PSD and no other musculoskeletal problem. Horses in Group 2 had primary PSD in association with straight hock conformation and/or hyperextension of the metatarsophalangeal joint. Horses in Group 3 had PSD and other problems contributing to lameness or poor performance. In Group 1, 70 of 90 horses (77.8%) had a successful outcome, whereas in Group 3, 23 of 52 horses (44.2%) returned to full function for >1 year. Complications included iatrogenic damage to the plantar aspect of the suspensory ligament, seroma formation, residual curb-like swellings and the development of white hairs. All horses in Group 2 remained lame. There is a role for neurectomy of the deep branch of the lateral plantar nerve and plantar fasciotomy for long-term management of hindlimb PSD, but a prerequisite for successful management requires recognition of risk factors for poor outcome including conformation features of straight hock or fetlock hyperextension.Equine Veterinary Journal 08/2011; 44(3):361-7. · 2.29 Impact Factor