Objective analysis of surgeons' ergonomy during laparoendoscopic single-site surgery through the use of surface electromyography and a motion capture data glove.

BACKGROUND: Adding to the ergonomic inconveniences already presented by traditional laparoscopy (LAP), laparoendoscopic single-site (LESS) surgery has been found to entail other more specific problems, including greater reduction in movement freedom, in-line vision with loss of triangulation, and greater proximity of instruments. The objective of this study was to evaluate surgeons' ergonomy during LESS surgery, through the study of muscular activity, wrist angle, and hand movements, and compare it with conventional laparoscopy. METHODS: The study group was composed by 14 experienced laparoscopic surgeons, all right-handed. Each one performed dissection tasks on a physical simulator through LAP and LESS approaches. For LAP, straight laparoscopic scissors and dissector were used, whilst for LESS articulating tip scissors and dissector were chosen. During both tasks, muscular activity of biceps brachii, triceps brachii, forearm flexors and extensors, and trapezius muscles was registered through surface electromyography. Simultaneously right-hand movements and wrist angles were obtained through a motion capture data glove (CyberGlove(®)), which allowed for the use of a modified RULA test applied to the recorded angles with subsequent establishment of risk levels for the wrist joint. RESULTS: Muscular activity for trapezius (LAP 6.94 ± 4.12 vs. LESS 11.32 ± 4.68; p ≤ 0.05) and forearm extensor muscles (LAP 9.2 ± 2.45 vs. LESS 37.07 ≤ 16.05; p ≤ 0.001) was significantly lower in conventional laparoscopy compared with LESS approach. No statistical significance was obtained between the different sensors, except in 3 of the 11 analyzed CyberGlove(®) sensors. The modified RULA test showed a score of 3 for laparoscopy (unacceptable), whereas for LESS a score of 2 was obtained (acceptable), with statistically significant differences between them (p ≤ 0.05). CONCLUSIONS: The LESS approach entails greater level of muscular activity in the trapezius and forearm extensor muscles, but we have found evidences of a better wrist position during LESS compared with traditional laparoscopy.

Decomposition and analysis of laparoscopic suturing task using tool-motion analysis (TMA): improving the objective assessment.

PURPOSE: The laparoscopic suturing task is a complex procedure that requires objective assessment of surgical skills. Analysis of laparoscopic suturing task components was performed to improve current objective assessment tools. METHODS: Twelve subjects participated in this study as three groups of four surgeons (novices, intermediates and experts). A box-trainer and organic tissue were used to perform the experiment while tool movements were recorded with the augmented reality haptic system. All subjects were right-handed and developed a surgeon's knot. The laparoscopic suturing procedure was decomposed into four subtasks. Different objective metrics were applied during tool-motion analysis (TMA). Statistical analysis was performed, and results from three groups were compared using the Jonckheere-Terpstra test, considering significant differences when P ≤ 0.05. RESULTS: Several first, second and fourth subtask metrics had significant differences between the three groups. Subtasks 1 and 2 had more significant differences in metrics than subtask 4. Almost all metrics showed superior task executions accomplished by experts (lower time, total path length and number of movements) compared with intermediates and novices. CONCLUSION: The most important subtasks during suture learning process are needle puncture and first knot. The TMA could be a useful objective assessment tool to discriminate surgical experience and could be used in the future to measure and certify surgical proficiency.

Anatomical changes due to pneumoperitoneum analyzed by MRI: an experimental study in pigs.

PURPOSE: Different effects on cardiovascular and respiratory systems and liver are associated with pneumoperitoneum. This study aimed to determine the morphological changes in the abdominal anatomy as a result of increased intra-abdominal pressure due to pneumoperitoneum using MRI. METHODS: Ten healthy female pigs were used in this study. MRI studies of the abdomen in supine position were made before the creation of pneumoperitoneum and 1 h after increasing the pressure to 14 mmHg. Changes in area, volume, and longitudinal and transverse length of the liver were measured. The diameters of the lumen of the abdominal aorta, the inferior vena cava and portal vein were observed in three positions along the abdominal cavity. The position of the diaphragm after the induction of pneumoperitoneum was also analyzed. RESULTS: After induction of pneumoperitoneum, volume and transverse length of the liver was significantly increased, while peak area was decreased. Stenosis in the aortic lumen was observed (P < 0.05). Longitudinal and transverse diameters of the portal lumen were reduced, but significant differences were only found in the longitudinal diameter. Alterations in the diameter of the inferior vena cava lumen were obtained in three analyzed positions, but differences were significant only in two of them. A mean cranial displacement of the diaphragm equal to 25 mm was also observed. CONCLUSION: Increasing abdominal pressure up to laparoscopic pressure (14 mmHg) provokes morphological changes in the liver, vascular structures and diaphragm. These changes could be related to functional alterations that different organs experience after the induction of pneumoperitoneum.