Anatomic Verification Of Operating Processes Of Treatments On Stenosing Tenosynovitis With Needle Knife

1. Objective:1.1 To observe the flexor tendinous sheath A1, and locat it from the skin. To measure the length of the proximal palm transverse striation and distal palm transverse striation from the flexor tendinous sheath A1, in order to provid the anatomic reference for treatments on trigger finger with needle knife.1.2 To verify the injury on fingers caused by several kinds of operating processes of treatments on trigger finger with needle knife, and to provide reliable anatomical basis for more reasonable use of needle knife.1.3 To observe the characteristics of the superficial radial nerve (SRN) aroud the tip of radial styloid (TRS) and the flexor pollicis longus muscle tendon and extensor pollicis short muscle tendon, and to measure the length of the SRN from the TRS and the sheathing canal on the TRS, in order to provid the anatomic reference for treatments on De Quervain disease with needle knife.2. Methods:2.1 Anatomy observation:2.1.1 The anatomy characteristics of the soft tissue were observed around the flexor tendinous sheath A1, especially the tendinous sheath A1 and mesotendon on 6 adult cadavers of upper limb. The width of the flexor tendinous sheath A1 and the length of proper palmar digital nerves and vesseles from central line of sheath A1 were measured. The length of distal and proximate sheath A1 from distal palm transverse striation was also observed.2.1.2 The nearest distance was measured, that was the SRN from the TRS on 5 adult cadavers of upper limb. The length of sheathing canal and the distal and proximate sheathing canal from the TRS was measured.2.2 To simulate the operation with needle knifeSeveral kinds of operating processes of treatments on trigger finger with needle knife were performed to operate in the area of metacarpophalangeal joints of 6 cadaveric specimens of upper limb, which were dissected to observe after operation. The common used several kinds of operating processes were as follows:2.2.1 The skin was pricked into from the palm away from tendon and the tip of knife reached to the surface of bone, then cut vertically. If the tendon was intumescent, it should be cut 1 to 5 times.2.2.2 The tip of knife was performed to reach to the flexor tendon and moved vertically for the first time, then moved horizontally. If the process of operating was easy to undergo, the operation was over. The cutting edge of the needle knife should be along the flexor tendon.2.2.3 The tip of knife was operated to cut into the tendon sheath, then moved vertically and horizontally. The tendon sheath was also shoveled from the surface of a phalange.2.2.4 The last process of operation included the above-mentioned procedure.2.2.5 The tip of knife was operated to reach to the surface of trochlea of tendon sheath, and move to distal end of it along the flexor tendon. Then trochlea of tendon sheath was cut apart vertically and so on.All statistical analyses were performed with the SPSS 13.0 package. All values are given as mean±standard deviation.3. Results:3.1 Anatomy observation:3.1.1 The average width of the flexor tendinous sheath A1 was 5.2mm in thumb, (7.2±0.1) mm in index finger, (7.0±0.2) mm in middle finger, (7.2±0.1) mm in ring finger, (6.0±0.2) mm in little finge and 7.0mm overall.3.1.2 The length of fibra bony sheath was approximately (34.0±0.2) mm and the length of distal sheathing canal from the TRS is (18.0±0.1) mm, (16.0±0.1) mm from another end. The nearest distance was about (22.4±0.1) mm along length wise and (7.8±0.1) mm transversal, which the SRN from the TRS.3.1.3 The vincula tendinum was a kind of connective tissue, which was connected with flexor tendon and parietal layer of tendon synovial sheath and also between bones of fingers and flexor tendon. There were minute nerves and blood vesseles in it.3.1.4 The surface of styloid process of radius was covered by ligaments in dorsum of wrist joint, which connected radialis of distal end of radius with styloid process of radius to form a fibra bony sheath, which abductor pollicis longus and extensor pollicis brevis were in it. The radialis and ulnaris of styloid process of radius were higher than the middle of it. The radialis and ulnaris of SRN branched separately over the styloid process of radius, which was 5cm away from TRS. And the length of radialis branch of SRN part from TRS was nearer than the one of the ulnaris branch.3.2 To simulate the operation with needle knife3.2.1 Test 1:The needle knife may not be avoided passing through the flexor tendon without touching. The flexor tendon was cut off partially when cutted 1 to 5 times and the tip of knife was performed to reach to the surface of bones of fingers, then the flexor tendon was broke through, because the flexor tendon was in the middle of bones of fingers. The knife was moved vertically and horizontally, then the result was that the flexor tendon and arteria digitalis were damaged, even cut off.3.2.2 Test 2:When the knife was moved horizontally, the proper palmar digital nerves and proper palmar digital arteries were damaged patially. The length of the proper palmar digital nerves and proper palmar digital arteries part from the middle of bones of fingers was about 4.0mm. If the needle knife was operated unupright, the rate of damaging the proper palmar digital nerves and proper palmar digital arteries was rising.3.2.3 Test 3:When the operating processes of cutting vertically and horizontally were performed especially horizontally, consequently the flexor tendon and arteria digitalis were damaged, even cut off. Shoveled from the surface of a phalange, the flexor tendon and mesotendon were also injured.3.2.4 Test 4:When the tip of needle knife was handled to reach to the surface of bones of fingers and move horizontally, not only the periosteum was damaged, but also damaged vincula tendinum and the flexor tendon.3.2.5 Test 5:When the edge of needle knife was handled to cut intermittent, the surface of the flexor tendon was scored too.In a word, the needle knife may damage the periosteum, and may not be avoided passing through the flexor tendon without touching. When the knife was moved vertically and horizontally, the flexor tendon and arteria digitalis were damaged, even cut off. Shoveled from the surface of a phalange, and the flexor tendon and mesotendon were also injured.4. Conclusion: There was no doubt that treatments on trigger finger with needle knife somehow had gotten advantages over other ones, but they also may cause unexpect complication, if the operaters were not familer with opography constitution, especially operating uncorrctly, because the treatents were with blindsight. There were reports in literatures that treatments with needle knife caused tendon rupture, and adhesion of tendon seriously afer operation, and recurrences of tenosynovitis and peripheral nerve injury, and infection of tissue, and so on. By test, the several kinds of operating processes of treatments above-mentioned can cause damages on flexor tendon and proper palmar digital nerves and vesseles and mesotendon and the periosteum.The main aim of treatments on trigger fingers with needle knife was at cutting apart the flexor tendinous sheath A1, and free of constraint of tendon. The flexor tendinous sheath A1 was a canle of fibra bony sheath, by which deep fascia in palmar gets thickening, and we found that deep fascia in anterior border and posterior border was thicker than other part, which may be related with bony process. So the operators needed only cut off the flexor tendinous sheath A1.The induration which was intumescent tendon due to constraint of tendinous sheath, was cut 1 to 5 times in test 1, that was an obviously detriment. Afer dissection, we found that the needle knife may not be avoided passing through the flexor tendon without touching. There was not nessasary that the tip of needle knife was used to reach the surface of bones of fingers, otherwise the periosteum and vincula tendinum and minute blood vesseles in vincula tendinum were damaged and it could increase the rate of adhesion of tendon after operation. There was also not nessasary that the tip of needled knife was used to reach to tendon, and moved vertically and horizontally in test 2, which may damage proper palmar digital nerves and vessles. In test 3 and 4, shoveled from the surface of a phalange, the flexor tendon and mesotendon were also injured.The theory of treatments on De Quervain disease with needle knife based on that the needle knife can remove the constraint of tendinous sheath and adhesion of tendon, in addition to injecting mixed liquor of local anesthetic and hormone, in order to eliminate inflammation and relieve pain and decrease adhesion of tendon, and so on. Bacause the nearest distance of the SRN from the TRS was appoximatly 7.0mm, if the needle knife was moved extensively, the SRN may be injured.Genarally, according to the characteristics of tendinous sheath in the styloid process of radius, the needle knife should be perpendicular to the bone surface, and also in parallel with the tendon with needle knife on De Quervain disease. While the needle knife should be moved about 2.0mm, and less than 7.0mm transversal from the TRS, otherwise the superficial radial nerve may be damaged. The operator should take care.