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- Lundborg, G, et al.
(författare)
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Tubular versus conventional repair of median and ulnar nerves in the human forearm : early results from a prospective, randomized, clinical study
- 1997
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Ingår i: The Journal of Hand Surgery. - 0363-5023. ; 22:1, s. 99-106
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Tidskriftsartikel (refereegranskat)abstract
- Injury to a peripheral nerve is followed by local synthesis and release of neurotrophic factors of importance for the regeneration process. This concept was adopted for repair of transected human median and ulnar nerves in the forearm. As an alternative to conventional microsurgical repair of the nerve trunk, silicone tubes of appropriate size were used to enclose the injury zone, intentionally leaving a gap measuring 3-4 mm between the nerve ends inside the tube. The early results from a prospective, randomized, clinical study comparing this principle with conventional microsurgical technique for repair of human median and ulnar nerves, is presented. Eighteen patients (14 men and 4 women), aged 12-72 (mean, 29.5) years, were randomized to either tubulization (11 cases) or conventional microsurgical repair (7 cases). A battery of tests for sensory and motor functions of the hand were carried out at regular intervals for up to 1 year after surgery. The results show no difference between the both techniques, with the exception of perception of touch, which showed a significant difference (p < .05) at the 3-month checkup in favor of the tubulization technique. At re-exploration 11 months after the initial procedure (1 case), the former gap was replaced by regenerated nerve tissue in direct continuity with the proximal and distal parts of the nerve trunk, the exact level of the former injury being impossible to identify. Study data demonstrate an intrinsic capacity of human major nerve trunks to reconstruct themselves in a preformed space when an optimal environment is offered and the surgical trauma is minimized.
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| 2. |
- Lieber, Richard L, et al.
(författare)
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Sarcomere length changes after flexor carpi ulnaris-to-extensor digitorum communis tendon transfer
- 1996
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Ingår i: Journal of Hand Surgery-American Volume. - New York : Churchill Livingstone. - 0363-5023 .- 1531-6564. ; 21:4, s. 612-618
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Tidskriftsartikel (refereegranskat)abstract
- Sarcomere length was measured intraoperatively on five patients undergoing tendon transfer of the flexor carpi ulnaris (FCU) to the extensor digitorum communis (EDC) for radial nerve palsy. The most significant result was that the absolute sarcomere length and sarcomere length operating range of the FCU increased after transfer into the EDC (p <.001). Preoperatively, with the wrist fully extended and fingers flexed, FCU sarcomere length was 4.22 +/- .24 mu m and decreased to 3.19 +/- .05 mu m as the wrist was fully flexed. This represented an overall sarcomere length range of 1.03 mu m After the tendon transfer using standard recommended techniques, all sarcomere lengths were significantly longer (p <.001). Specifically, sarcomeres were 0.74 +/- .14 mu m longer with the muscle in its fully lengthened position (4.96 +/- .43 mu m with the wrist and digits flexed) and 0.31 +/- .16 mu m longer with the FCU in the fully shortened position (3.50 +/- .06 mu m with the wrist and digits extended). At these sarcomere lengths, the FCU muscle was predicted to develop relatively high force only during movement involving synergistic wrist flexion and finger extension. Under the conditions of the procedures performed, the transferred FCU muscle was predicted to produce maximum force over the range of about 30 degrees of wrist flexion and 0 degrees of finger flexion to 70 degrees of wrist extension and 90 degrees of finger flexion. While this is acceptable, a more desirable result was predicted to occur if the muscle was transferred at a longer length. In this latter case, greater stretch of the FCU during transfer (increasing sarcomere length to about 5 mu m) was predicted to improve the transfer. The more highly stretched FCU was predicted to result in maximum force as the wrist and fingers progressed from about 60 degrees of wrist extension and 0 degrees of finger flexion to 80 degrees of wrist extension and 70 degrees of finger flexion. These results quantify the relationship between the passive tension chosen for transfer, sarcomere length, acid the estimated active tension that can be generated by the muscle. The results also demonstrate the feasibility of using intraoperative laser diffraction during tendon transfer as a guide for optimal placement of the transferred muscle.
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