Ulnar Nerve Strain in Functional Elbow and Shoulder Motions.

Background: Shoulder and elbow motions can affect ulnar nerve strain. However, there is no evidence that links this kind of strain to specific activities. The purpose of this study was to examine ulnar nerve strain at the elbow resulting from normal daily activities. Methods: This study was conducted using thirty fresh frozen cadaveric elbows from subjects who had no deformities or history of previous upper extremity surgery. Strain was calculated based on nerve elongation. Ulnar nerve strain at the elbow from motion related to common daily activities was measured in both normal nerves and nerves in which gliding motion was restricted. The results of these measurement were then compared. Results: Activities related to extreme elbow and shoulder motions, such as cellular phone use, yielded an average strain of 6.3%. In addition, we found that nerve strain increased significantly in conditions in which gliding motion was restricted. Nerve strain due to motion associated with cellular phone use, for example, rose by 69.1%. Conclusions: Elbow flexion and shoulder abduction in daily activities are associated with increases in ulnar nerve strain, but this may not cause permanent damage to the nerve. After nerve gliding motion had been restricted, nerves that normally exhibited less strain often had even increased higher levels of strain than those nerves that normally exhibited high strain.

Distal anastomosis patterns of the descending branch of the lateral circumflex femoral artery.

BACKGROUND: The reverse anterolateral thigh (ALT) flap has shown good results in the treatment of patients who have skin and soft tissue defects around the knee and shin. The objective of this study was to show the anastomotic patterns of the descending branch of lateral femoral circumflex artery (db-LCFA) and locate the appropriate pivot point for reverse ALT flap. MATERIALS AND METHODS: Fifty thighs from 25 embalmed cadavers from the Anatomy Department, Khon Kaen University in 2012, were dissected. The patterns of distal anastomoses of db-LCFA were recorded and appropriate pivot points for the reverse ALT flap were measured. RESULTS: Three patterns of distal anastomosis of the db-LCFA were identified, including the anastomoses to the superolateral genicular arteries (46%), anastomoses to the profunda femoral arteries (28%), and unidentified distal anastomoses (26%). The mean distance of the pivot point was 9.4 ± 3.7 cm from the lateral epicondyle. The mean pedicular length was 13.2 ± 5.4 cm (mean ± SD). Most cadavers, 76%, showed a single db-LCFA. In cases where there was more than one db-LCFA, the distal anastomoses were found to be originating from the most medial db-LCFA. CONCLUSION: The reverse ALT flap technique showed good results in the treatment of patients with skin and soft tissue defects around the knee and shin. Variations of the anastomoses and branching patterns of the db-LCFA may influence flap survival. Additional preoperative vascular evaluations would be helpful in defining the most compatible area from which to harvest the flap.

Validity of the Thai version of Disability of the Arm, Shoulder and Hand Questionnaire (KKU-DASH) in patients with brachial plexus injury.

OBJECTIVE: To assess the reliability and validity of the Thai version of the Disability of the Arm, Shoulder and Hand (KKU-DASH) questionnaire in patients with brachial plexus injuries. MATERIAL AND METHOD: The Thai KKU-DASH version was performed based on translation/back translation methodology. Thirty-four Thai-speaking patients with brachial plexus injuries completed the KKU-DASH and the 36-item short-form health survey (SF-36) questionnaires preoperatively and then were reassessed for test-retest reliability two months later Reliability was investigated for reproducibility and internal consistency The validity was evaluated by using component analysis and the correlations coefficients between the KKU-DASH and the SF-36. RESULTS: The internal consistency of the degree of difficulty, severity of pain, and social activity domains of the KKU-DASH was good to excellent (Cronbach's alpha 1.00, 0.75, and 1.00). The intraclass correlation coefficient (ICCs) for the test-retest reliability was 0.52. For the degree ofdifficulty, severity of pain, social activity, and psychological effect on self-image, the ICC were 0.5, 0.45, 0.57, and 0.53 respectively The convergent validity between the KKU-DASH and SF-36 was -0.76. The convergent validity of each domain between both instruments ranged from 0.46 to 0.69 and the strongest correlation was observed in the social activity domain. CONCLUSION: According to the reliability and validity testing, the KKU-DASH questionnaire is suitable for Thai-speaking patients with brachial plexus injuries.

Anatomical study of arcade of Struthers.

The incidence and the anatomical location of the arcade of Struthers as related to the arm length were studied in 62 arms of adult fresh-frozen cadavers. The distance between the greater tuberosity and the lateral epicondyle was designated as the arm length. The arcades of Struthers were identified in 85.4%. The mean arm length was 27.85 ± 1.3 cm. The mean of the distance between proximal border of the arcade of Struthers and the medial humeral epicondyle was 8.24 ± 2.06 cm. The mean ratio between the distance from the proximal border of the arcade to the tip of the medial epicondyle and arm length was 0.29 ± 0.07. We concluded that the anatomical location of the arcade as related to the arm length was 29% proximally, from the tip of the medial epicondyle. This report of the anatomical location of the arcade of Struthers related to the arm length can be useful to identify this structure in the arms which have differences in arm length during the surgical exploration and anterior transposition of the ulnar nerve procedures.

Intra-tendon sheath injection for trigger finger: the randomized controlled trial.

The most common technique used for non-surgical treatment of trigger fingers is the direct injection of steroids into the flexor tendon sheath over the metacarpal head. However, this method causes more pian to the patient and can result in tendon rupture due to insertion of needle into the tendon. Carlson and Curtis described the mid-axial injection technique which is simple and relatively painless. We aim to compare the pain result from the injection between these two methods. The prospective randomised control trial study was designed. There were 103 trigger fingers included in the study which were divided into two groups: the conventional technique of injection (CI technique) and the mid-axial injection technique (MAI technique). The visual analogue scale for pain score had been recorded at the time of injection: one, three and six weeks. The complication after injection and the recurrent symptoms within one year were also recorded. The Student's t-test, Chi-squared and Fisher-exact analysis were used for statistical testing. The results showed that the mean VAS pain scores immediately after needle insertion were 40.19 +/- 23.3 and 48.39 +/- 26.5 in the MAI and CI technique groups, respectively. The MAI technique was less painful than the CI technique (p < 0.05). There were no complications from the injections in both methods. However, the recurrent rate seems to be higher in the conventional technique (p = 0.23). We concluded that the MAI injection technique provided less pain result than the CI technique and there were no complications from this injection technique.

Anatomic safe zone for proximal ulnar fixation: a cadaver study.

OBJECTIVE: To study the location and characterization of the safe zone with respect to bony landmarks on volar surface of proximal ulna for the protrusion of various ulnar fixations. MATERIAL AND METHOD: The present study was done on 39 upper extremities from 20 embalmed human, adult cadavers. The average ages of the cadavers were 67.28 +/- 10.96 years (range from 40 to 82 years), 10 females, and 29 males. The safe zone dimensions, both in coronal and sagittal planes, were measured. RESULTS: The distance between median nerve and volar surface of proximal ulna in sagittal plane at 2 cm and 4 cm distal to tip of coronoid process were 0.99 +/- 0.15 cm (range from 0.76-1.32 cm) and 0.85 +/- 0.17 cm (range from 0.64-1.75 cm), respectively. The distances between the lateral border of the proximal ulna and medial border of the median nerve in coronal plane at 2 cm and 4 cm distal to the tip of the coronoid process were 0.95 +/- 0.19 cm (range from 0.66-1.36 cm) and 0.82 +/- 0.14 cm (range from 0.52-1.14 cm), respectively. CONCLUSION: Based on the present results, if intra-medullary screws or K-wire fixations were used, it should theoretically be long enough to reach their proximal ulna in order to bite into the cortical bone, but should not be so long as to cut out into its lateral part and, in the sagittal plane, the protrusion should not be longer than 0.92 cm. Orthopedic surgeons must remain vigilant with regard to any types of fixation in the upper extremity because the risk of neurovascular injury is high.

Vascular anatomy of the proximal fibula from embalmed cadaveric dissection.

OBJECTIVES: To study the vascular pattern of proximal fibula with use of embalmed cadaveric specimens. MATERIAL AND METHOD: The present study was done on 33 lower extremities from 19 embalmed human, adult cadavers. The average ages of the cadavers were 68.6 years (range from 36 to 98 years), 11 females and 8 males. The size and site of vessels around the proximal fibula were recorded. RESULTS: There were three main blood supplies of proximal fibular the epiphyseal artery, the lateral genicular artery, and the periosteal blood supply. They are anterior tibial recurrent artery and posterior tibial artery or artery of the neck of fibula posteriorly. Inferior lateral genicular artery was seen in all specimens (33/33). Among them, 42.4% (14/33) had a single artery with double accompanied veins. The average diameter of artery and veins were 1.71 mm (0.75-2.25), and 1.69 mm (1.30-2.10), respectively. The others were single artery and single vein. The average diameter ofartery and veins were 1.66 mm (0.65-2.14), and 2. 1 mm (0. 95-2.30) respectively. Anterior tibial recurrent artery was seen in 31 of 33 specimens (94%). The average size of artery and accompanying vein were 1.24 mm (0.8-2.1), and 1.86 mm (0.8-2.6), respectively. Posterior tibial recurrent artery was an inconsistent branch that appeared in only 11 of 33 specimens (33%). Artery of the neck of fibula appeared in 24 of 33 specimens (72.7%). The others were replaced by the predominant posterior tibial recurrent artery (7/33) and neither of them was found in two specimens. CONCLUSION: Based on the present results, the authors recommend preserving the epiphyseal blood supply, the inferior lateral genicular artery, and the periosteal blood supply for free epiphyseal transfer In addition, surgeons should pay attention to the variation of posterior periosteal blood supply because its variations will affect the viability percentage of proximal fibular epiphyseal transfer.

A comparative biomechanical study of the looped square slip knot and the simple surgical knot.

The looped square slip knot was introduced as a technique for skin closure to avoid the use of sharp instruments in suture removal after hand surgery. We compared the biomechanical properties of this knot with the simple surgical square knot. The ultimate strength of the looped square slip knot was significantly (p = 0.015) higher than the simple surgical knot. There was no significant difference between the two knots in mode of failure. Knot slippage or suture breakage did not occur in any samples when testing security by repetitive loading. Therefore, the looped square slip knot is a safe and convenient alternative to the two-throw surgical knot for use in hand surgery.

Congenital metacarpal synostosis treated by double bone blocks technique: a case report from Thailand.

Congenital metacarpal synostosis is a rare congenital anomaly in the hand, especially in our area. There were several reports of surgical techniques for correction deformities. We report this rare condition in our hospital and treatment with the metacarpal osteotomy and double bone blocks technique of grafting.