Tenovaginoscopic approach to the common digital flexor tendon sheath of adult cattle: technique, normal findings and preliminary results in four clinical cases

The aim of this study was to describe the tenovaginoscopic approach to the bovine common digital flexor tendon sheath (CDFTS). A comparative anatomical, ultrasonographic and endoscopic study was undertaken using 26 healthy cadaver feet from adult dairy cows. Tenovaginoscopy was performed using a rigid, 30 degrees arthroscope (length 18 cm; outer diameter 4mm) enabling a direct view of the synovial cavity and the following structures: digital flexor tendons, digital annular ligaments, lateral and medial pouches, three mesotendons, the vinculum of the superficial digital flexor tendon, and a slot-shaped opening in the manicaflexoria of the hind feet. Additionally, four clinical cases of septic tenosynovitis treated with lavage under tenovaginoscopic control were examined. Tenovaginoscopy represents a feasible, minimally invasive method for the diagnosis and treatment of septic tenosynovitis of the CDFTS, which allows the degree of alterations of the normal structures to be evaluated.

FDG uptake in giant cell tumor of the tendon sheath in a patient restaged for gastrointestinal stroma tumor (GIST)

A 70-year-old man known for recurrent abdominal gastrointestinal stroma tumor presented with a suspicious peritoneal mass demonstrated by an abdominal CT scan. Whole-body PET showed focal FDG uptake in the right hip, whereas the peritoneal mass was FDG negative. Histologic work-up of the PET positive lesion surprisingly revealed a giant cell tumor of the tendon sheath. The benignity of the peritoneal mass was confirmed by its disappearance in repeated CT scans. In general, focally increased FDG uptake should be subject to further investigations, especially in localizations that are not consistent with typical metastatic pathways of the former primary tumor.

Distribution of radiodense contrast medium after perineural injection of the palmar and palmar metacarpal nerves (low 4-point nerve block): an in vivo and ex vivo study in horses

REASONS FOR PERFORMING STUDY: Evidence-based information is limited on distribution of local anaesthetic solution following perineural analgesia of the palmar (Pa) and palmar metacarpal (PaM) nerves in the distal aspect of the metacarpal (Mc) region ('low 4-point nerve block'). OBJECTIVES: To demonstrate the potential distribution of local anaesthetic solution after a low 4-point nerve block using a radiographic contrast model. METHODS: A radiodense contrast medium was injected subcutaneously over the medial or the lateral Pa nerve at the junction of the proximal three-quarters and distal quarter of the Mc region (Pa injection) and over the ipsilateral PaM nerve immediately distal to the distal aspect of the second or fourth Mc bones (PaM injection) in both forelimbs of 10 mature horses free from lameness. Radiographs were obtained 0, 10 and 20 min after injection and analysed subjectively and objectively. Methylene blue and a radiodense contrast medium were injected in 20 cadaver limbs using the same techniques. Radiographs were obtained and the limbs dissected. RESULTS: After 31/40 (77.5%) Pa injections, the pattern of the contrast medium suggested distribution in the neurovascular bundle. There was significant proximal diffusion with time, but the main contrast medium patch never progressed proximal to the mid-Mc region. The radiological appearance of 2 limbs suggested that contrast medium was present in the digital flexor tendon sheath (DFTS). After PaM injections, the contrast medium was distributed diffusely around the injection site in the majority of the limbs. In cadaver limbs, after Pa injections, the contrast medium and the dye were distributed in the neurovascular bundle in 8/20 (40%) limbs and in the DFTS in 6/20 (30%) of limbs. After PaM injections, the contrast and dye were distributed diffusely around the injection site in 9/20 (45%) limbs and showed diffuse and tubular distribution in 11/20 (55%) limbs. CONCLUSIONS AND POTENTIAL RELEVANCE: Proximal diffusion of local anaesthetic solution after a low 4-point nerve block is unlikely to be responsible for decreasing lameness caused by pain in the proximal Mc region. The DFTS may be penetrated inadvertently when performing a low 4-point nerve block.

Clinical primary flexor tendon repair and rehabilitation: The Bern Experience

In this chapter we present our experience with treatment of zone 2 flexor tendon repair using a six-strand repair technique combined with postoperative place-and-hold exercise. The six-strand Lim/Tsai repair technique combined with place-and-hold exercises demonstrated better digital function compared to a two-strand repair without place-and-hold exercises. Range of motion in the Lim/Tsai repair group appeared to be increased without a higher rate of ruptures but with a shorter rehabilitation period. The fact that the two groups differed in both suture techniques and rehabilitation programs made it impossible to know whether the better results in the group of Lim/Tsai were due to the six-strand repair or the place-and-hold exercises or both. Despite the obvious benefit of early active mobilization, an active motion protocol may not always be possible to apply in a substantial number of patients due to concomitant injuries, the quality of the surgical repair or patient factors (swelling, pain, limited compliance). Since August 2006 a staged rehabilitation program (“stop and go”) was introduced within our unit using early active controlled flexion (green), place-and-hold (yellow), or passive flexion exercises (red) introduced by Kleinert-Duran. Our experience using the six-strand suture repair technique and “stop and go” is outlined.

Diseases of the Tendons and Tendon Sheaths

Contracted flexor tendon leading to flexural deformity is a common congenital defect in cattle. Arthrogryposis is a congenital syndrome of persistent joint contracture that occurs frequently in Europe as a consequence of Schmallenberg virus infection of the dam. Spastic paresis has a hereditary component, and affected cattle should not be used for breeding purposes. The most common tendon avulsion involves the deep digital flexor tendon. Tendon disruptions may be successfully managed by tenorrhaphy and external coaptation or by external coaptation alone. Medical management alone is unlikely to be effective for purulent tenosynovitis.