Chapter 84 - Tendon part II surgical tx Flashcards
what was the % of horses that return to racing after desmotomy of ALSDFT?
SDFT tendinopathy treated by DALSDFT returning to racing.
What condition often involves the PAL in horses?
Tenosynovitis of the Digital Flexor Tendon Sheath (DFTS).
Why is the term “PAL syndrome” used?
Due to the difficulty in differentiating primary PAL issues from secondary effects of tenosynovitis.
When is PAL desmotomy indicated?
When PAL constriction impedes flexor tendon function and conservative treatment fails.
Why might PAL desmotomy improve tenoscopic procedures in the DFTS?
It creates more space for maneuvering instruments.
What is a potential downside of open PAL desmotomy?
Risk of wound dehiscence and potential complications like septic tenosynovitis.
What is a benefit of the limited open approach for PAL desmotomy?
It can be done on a standing animal without general anesthesia.
Describe in detail the surgical procedure of SDFT tendinopathy transection of the acessory ligament
With the horse in dorsal or lateral recumbency and the affected limb partially flexed, centesis and distension of the carpal sheath is performed before a tenoscopic portal is created into the carpal sheath 2 to 3 cm proximal to the distal radial physis on the lateral side of the limb, between the ulnaris lateralis and lateral digital extensor muscles. An instrument portal is made immediately proximal to the distal radial physis. A probe is used to palpate the distal and proximal limit of the subsynovially located accessory ligament, which is subsequently transected using a No. 10 scalpel blade on a long handle, a meniscectomy knife, or a tenotomy knife. The ligament is severed directly over the flexor carpi radialis tendon (Figure 84-20). The very proximal portion of the ligament cannot be visualized directly because it extends proximad to the synovial reflection of the carpal sheath. For this proximal portion, careful dissection using punch biopsy forceps is needed for transection, taking care to avoid the perforating blood vessel at the proximal limit of the accessory ligament. Alternatively, transection can also be performed using electrosurgical instruments such as loop-headed or hook-headed monopolar electrodes or bipolar radiofrequency probes.
Figure 84-20. Endoscopic view obtained during tenovaginoscopic desmotomy of the ALSDFT via standard lateral tenoscope and instrument portals. The horse is in dorsal recumbency and distal is on top of the image. The distal parts of the ALSDFT are already transected with a radiofrequency probe exposing the flexor carpi radialis (labeled FCR in the image) tendon. The proximal part of the ALSDFT is still intact (labeled USB-OBS in the image). The DDFT is visible caudally.
What are the 3 tx of PAL transection?
open standing
open GA
Tenoscopic tx
What tool is typically used in tenoscopic PAL transection?
A hooked knife or slotted cannula.
How does radiofrequency probe usage impact the outcome of PAL desmotomy?
It reduces hemorrhage but may cause cellular damage and affect prognosis.
describe the standing open approach of PAL desmotomy
The open approach is performed under general anesthesia in lateral recumbency. The paramedian skin incision extends over the entire length of the PAL slightly abaxially to the palmar/plantar midline. Dissection through the subcutaneous tissue is directed towards the palmar/plantar midline to allow transection of the PAL at the level of the mesotenon and division of adhesions, if required. Routine closure of the subcutis and skin is subsequently performed.with a 1- to 2-cm-long skin incision at the proximal border of the PAL and transection of the ligament with a curved bistoury or a scalpel blade guided by a curved instrument or a groove director.
Figure 84-21. Tenovaginoscopic view showing transection of the PAL using a hook knife. Note the dense and transversely oriented fibers of the PAL palmarly (left side of the image) and the palmar aspect of the SDFT on the right side of the image.
Figure 84-22. The use of the slotted cannula for transection of the PAL. (A) The cannula is guided through the sheath from proximal to distal under arthroscopic control to ensure that it does not lie inside the manica flexoria. (B) The central obturator is removed and a hook knife is introduced (knife not shown) to cut the PAL via the slot in the cannula. This can be introduced from either a proximal or a distal direction, with the arthroscope (without its sleeve) in the opposite end to view the procedure. This technique allows closed and accurate transection of the ligament without damaging other structures.
Figure 84-23. Commonly detected abnormalities that cause tenosynovitis of the digital sheath. (A) Surface tear (arrow) of the DDFT, most commonly found in forelimb tenosynovitis. (B) Rupture (arrow) of the attachments of the manica flexoria, most frequently seen in hind limb tenosynovitis.
What tendon is more affected in DFTS tenosynovitis in the forelimbs?
The Deep Digital Flexor Tendon (DDFT).
What imaging technique helps identify DDFT tears?
Ultrasonography, though sensitivity is limited.
Why might contrast radiography be used before PAL desmotomy?
To identify tendon tears and other intrathecal lesions.
Where are Manica Flexoria (MF) tears most common?
At the medial attachment to the Superficial Digital Flexor Tendon (SDFT).
What is the success rate of tenoscopic MF removal for return to activity?
Approximately 80%.
What is a common complication after MF debridement?
Poor outcomes if treated without full resection.
How long is rest recommended after DFTS tenoscopy?
At least 2 weeks, with a gradual increase in hand-walking duration.
What diagnostic tool improves visualization of DDFT tears in weight-bearing views?
Contrast-enhanced ultrasonography.