Faculty Bibliography

A new approach to achieve digital block by use of the flexor tendon sheath as an avenue introducing anesthetics to the core of the digit is described. Through centrifugal anesthetic diffusion all four digital nerves are anesthetized rapidly. This technique involves palmar percutaneous injection of 2 ml of lidocaine (Xylocaine) into the potential space of the flexor tendon sheath at the level of the palmar flexion crease with a 3 ml syringe and a No. 25-gauge hypodermic needle. Over the last 5 years, I have used this technique on 420 patients with no observable anesthetic complication. A repeat injection or local infiltration as a supplement was necessary only in four instances.

Neurite promoting factors (NPF), fibroblast growth factor, and laminin were instilled inside autologous venous nerve conduits (AVNC) interposed across a 1 cm gap in the rat sciatic nerve. Axonal regeneration was measured electrophysiologically and histologically and was compared to control AVNC and autologous nerve grafts (ANG) in 45 rats. By 1 month, the AVNC group with NPF recovered an average nerve conduction velocity twice that of the ANG group (24 m/sec vs. 12 m/sec). The gastrocnemius muscle action potential of NPF grafts was twice that of the control AVNC and was similar to the ANG (1.63 mV vs. 0.87 mV). In subsequent months, the advantage of NPF disappeared; these grafts were grossly reduced to fibrous bands. Histological examination of these grafts at 5 months revealed a florid intraluminal fibrovascular proliferation, which appeared to be "choking off" the regenerating axons. It is suggested that more refined mixtures of NPF should be instilled inside AVNC so that the improved axonal regeneration is maintained while the late inhibitory fibrosis is avoided.

The choice between repair or reconstruction in the management of nerve injury, and the determination on timing and the type of neurorrhaphy technique are clinical decisions that should be based on thorough understanding of the pathophysiology of nerve injury, the physiology of nerve healing, and the anatomy of peripheral nerves. The formulation of a treatment plan should be individualized.

This article presents a successful replantation of a completely severed rat ear. The procedure include re-union of the tubal cartilage and anastomosis of the surgically divided external carotid artery and posterior facial vein.

Looking ahead, one envisions an era of remarkable progress in the study of the healing of bone and cartilage. The physical, biochemical, and biomechanical factors governing bone and cartilage healing will be defined and manipulated to accelerate the healing process. Joint stiffness, the undesirable sequela of many simple fractures of the hand as a result of prolonged immobilization, will be obviated. For cases of limited joint damage, techniques for joint reconstruction will be refined. For non-salvageable bone and joint destruction, microvascular allogenic transplantation of skeletal units will become a reality. Silastic implants in the wrist will become historical oddities.

This is an experimental study comparing the suturing time and patency rate of a spiral interrupted suturing technique to those of conventional interrupted and continuous suturing technique in end-to-end as well as end-to-side anastomosis. The spiral interrupted suturing technique requires less time for either end-to-end or end-to-side anastomosis than conventional interrupted suturing technique, and does not result in stenosis as shown in the venous end-to-end anastomosis by continuous suturing technique.