Immediately after a tendon repair, the tendon contributes nothing to the strength of repair. During that time, the suture itself and suture technique are the sole contributors to the strength of repair. Although stainless steel is the strongest material that can be used at the time of repair, it has serious disadvantages. It is difficult to work with and makes a bulky knot. Conversely, all absorbable sutures become too weak too soon to be of value. At this time, nonabsorbable, synthetic fibers that are relatively strong, such as Supramid or prolene, are the most desirable materials available. Regarding suture techniques, the lateral trap and end-weave techniques produce the strongest repairs; however, the end-weave technique can only be used with tendon grafts and the lateral trap, though it can be used for end-to-end primary repairs. It is too bulky for use in the fingers and hand but is ideal for the forearm and wrist. In the hand and fingers, the strongest repair techniques available are the Bunnell, Kessler, and Mason-Allen; however, the Bunnell stitch is more strangulating to the microcirculation of the tendon than the latter two stitches; thus, it contributes to tendomalacia and gap formation. The simplest and least traumatic suture technique, though weakest at first, will allow tendon healing to proceed more rapidly. If such a repair is protected from tension by splinting the wrist and metacarpophalangeal joints in flexion during healing (while allowing controlled passive motion of the finger joints), there will be a rapid increase in tensile strength of the tendon juncture with minimal gap formation, as the repaired hand is progressively stressed up until about 90 days postrepair. At that point, strength plateaus and maximum stress can be applied to the repaired tendon. Somewhere between three and six weeks post-tendon repair, the suture material and technique become secondary to tendon healing as the primary provider of tensile strength to the tendon wound. The less traumatic suture techniques facilitate closure of the tendon sheath, which not only acts as a mechanical barrier to the ingrowth of extrasheath adhesion, which produces fibroblasts, but also re-establishes the continuity of the synovial fluid system, which is a major source of nutrition to the tendon. The healing tendon then can be thought of as a delicate structure, one not to be overmanipulated, traumatized, strangulated, or stretched.(ABSTRACT TRUNCATED AT 400 WORDS)