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Vikas Dhawan

Publications and source records attributed to Vikas Dhawan.

6 recordsLinked to original sources

A benefit of the volar approach for wrist arthroscopy.

We reviewed 230 cases of wrist arthroscopy using a volar approach and evaluated its advantage in various wrist disorders. In general, a dorsal approach has been preferred in wrist arthroscopy. The volar approach has been avoided because of the presence of significant structures, such as radial and ulnar arteries, their venae comitantes, median and ulnar nerves, and flexor tendons. However, we can access the wrist joint securely using the volar approach through the tendon sheath of the flexor carpi radialis. Through this approach, we can adequately visualize the dorsal rim fragment of the intra-articular fracture of the distal radius, dorsal synovial proliferation of the rheumatoid wrist, and volar segment tear of the scapholunate and lunotriquetral interosseous ligaments. We had no complications with wrist arthroscopy using the volar approach in 230 patients. The volar approach for wrist arthroscopy is a valuable procedure to evaluate and treat various wrist disorders.

Adult↗

Arthroscopic assessment of the volar region of the scapholunate interosseous ligament through a volar portal.

PURPOSE: The volar region of the scapholunate interosseous ligament is one of the key structures that maintains scapholunate alignment. It is, however, difficult to evaluate this ligament using standard diagnostic procedures, including the arthroscopy through a dorsal portal. We have performed arthroscopic evaluation of this ligament through a volar portal. METHODS: Skin incision was made at just radial of the flexor carpi radialis tendon and the portal was opened through the tendon sheath. RESULTS: The volar approach enabled us to directly observe the extent of the tear of the volar region of scapholunate interosseous ligament. A shaver is inserted through the dorsal portal, and debridement can be performed by using the volar portal vein. We have not had any complications using volar portal. CONCLUSION: Volar approach is a feasible and safe procedure to evaluate and treat the volar region of the scapholunate interosseous ligament.

Arthroscopy↗

Significance of venous anastomosis in fingertip replantation.

Adequate venous outflow is the most important factor for successful fingertip replantation. The authors have attempted venous anastomosis in all cases of fingertip replantation to overcome postoperative congestion. In this article, the significance of venous repair for fingertip replantation is described from the authors' results of 64 complete fingertip amputations in 55 consecutive patients, which were replanted from January of 1996 to June of 2001. The overall survival rate was 86 percent. Of the 44 replantations in zone I, 37 survived, and the success rate was 84 percent. Of the 20 replantations in zone II, 18 survived, and the success rate was 90 percent. Venous anastomosis was attempted in all cases, but it was possible in 39 zone I and in all zone II replantations. For arterial repair, vein grafts were necessary in 17 of the 44 zone I and in one of the 20 zone II replantations; for venous repair, they were necessary in six zone I replantations and one zone II replantation. Postoperative vascular complications occurred in 15 replantations. There were five cases of arterial thrombosis and 10 cases of venous congestion. Venous congestion occurred in nine zone I and one zone II replantations. In five of these 10 replantations, venous anastomosis was not possible. In another five replantations, venous outflow was established at the time of surgery, but occlusion occurred subsequently. Except for the five failures resulting from arterial thrombosis, successful venous repair was possible in 49 of 59 replantations (83 percent). Despite the demand for skillful microsurgical technique and longer operation time, the authors' results using venous anastomosis in successful fingertip replantations are encouraging. By performing venous anastomosis, external bleeding can be avoided and a higher survival rate can be achieved. Venous anastomosis for fingertip replantation is a reliable and worthwhile procedure.

Adolescent↗

The use of end-to-side nerve grafts to reinnervate the paralyzed orbicularis oculi muscle.

Facial paralysis is a serious neurologic disorder, particularly when it affects the eye. Loss of the protective blink reflex may lead to corneal ulceration and, possibly, visual loss. The purpose of this study was to compare different nerve-grafting techniques to reanimate the paralyzed eyelid. Sixteen adult dogs (25 kg each) were allocated into four groups. Denervation of the left hemi-face was performed in all cases. One dog served as a control animal (group I). Group II dogs (n = 5) underwent end-to-side coaptation of the nerve graft to the intact palpebral branch and end-to-end coaptation to the denervated palpebral branch. Group III dogs (n = 5) underwent end-to-end coaptation of the nerve graft to the intact palpebral branch and end-to-end coaptation to the denervated palpebral branch. Group IV dogs (n = 5) underwent end-to-side coaptation of the nerve graft to the intact and denervated palpebral branches. The animals were monitored for 9 months after the surgical procedures, to allow adequate time for reinnervation. The dogs were postoperatively monitored with clinical observation, electrophysiologic testing, video motion analysis, and histologic assessments. Clinical observation and electrophysiologic testing demonstrated the production of an eye blink in the denervated hemi-face in all experimental groups. There was a trend toward increased speed of reinnervation for group III animals (end-to-end coaptations). It was concluded that end-to-side coaptation can produce a contralateral synchronous eye blink in a clinically relevant, large-animal model.

Animals↗

Basic science behind functioning free muscle transplantation.

Free muscle transfer is now a feasible procedure in several fields of reconstructive surgery. In this article, basic science behind clinical free muscle transfer, including essential aspects like donor muscle selection (type of blood supply, architecture of fibers, fiber length, and muscle volume), donor nerve selection, placement and routing of muscle, tension of muscle at suturing, postoperative monitoring of muscle circulation, postoperative reinnervation, and rehabilitation are discussed in detail.

Facial Paralysis↗