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PubMed1994

Open surgical revision of laparoscopic pelvic lymphadenectomy for staging of prostate cancer: the impact of laparoscopic learning curve.

We attempt to clarify the impact of the learning curve on the first 30 laparoscopic pelvic lymphadenectomies performed at our institute. Open surgical revision of the area of laparoscopic dissection was performed at radical retropubic prostatectomy. The mean number of obturator and iliac lymph nodes removed laparoscopically was 8.7 and 8.8 from the right and left sides, respectively. The mean number of residual obturator and iliac lymph nodes removed at open operation was 3.2 and 3 from the right and left sides, respectively. The amount of residual lymph node tissue after laparoscopic lymphadenectomy progressively decreased with time, especially after the first 20 cases. A microscopic pelvic lymph node metastasis was found at open operation in patients 6, 14 and 15, who had false-negative results at laparoscopy. Due to the learning curve effect, the first 30 patients who undergo laparoscopic pelvic lymphadenectomy should be assessed again by an open operation at radical retropubic prostatectomy.

Aged↗

PubMedDate not supplied

Evaluation of the learning curve for laparoscopic Roux-en-Y gastric bypass surgery.

BACKGROUND: The literature reports that the learning curve for laparoscopic Roux-en-Y gastric bypass (LRYGBP) is approximately 75-100 cases. This aim of the present study was to evaluate the safety and feasibility of shortening the learning curve for performing LRYGBP by an experienced laparoscopic surgeon. METHODS: This study analyzed retrospectively the first 100 consecutive LRYGBP cases performed by an experienced laparoscopic surgeon between April 2003 and September 2003. The surgeon performed these cases after first assisting in 30 cases, and the first 4 cases were proctored by an experienced laparoscopic bariatric surgeon. Two cases done after previous gastric stapling and Nissen fundoplication were excluded from the study. Outcome variables included operative time, complications, conversion, and mortality. RESULTS: For the first 100 LRYGBP patients, the mean age was 42.6 years (range, 22-62 years) and mean body mass index (BMI) was 47.6 kg/m2 (range, 36-71.8). The complications included 1 case of intestinal leak, 1 case of small bowel obstruction, 6 cases of gastrojejunal stenosis, 8 cases of wound infection, 1 case of wound seroma, and 2 cases of pulmonary embolism, resulting in 1 mortality. One case was converted to an open technique. Over the second 50 cases, there was a significant reduction in mean operative time, to 73 minutes (range, 39-145 minutes) from 113 minutes (range, 54-238 minutes) (P < .0001). However, despite the reduction in complication frequency (no gastrointestinal leak or obstruction, 2 cases of gastrojejunal stenosis, 2 cases of wound infection, no pulmonary embolism/deep venous thrombosis, and no mortality), there was no significant correlation between the mortality, conversion, and complication rates and the surgeon's experience. CONCLUSION: A bariatric surgical practice incorporating LRYGBP can be safely done by an experienced laparoscopic surgeon. With appropriate advanced laparoscopic skills, preparatory steps, proctorship, and adequate volume of cases, the learning curve for performing LRYGBP can be reduced to 50 cases. Further experience is associated with a significant reduction in operative time with acceptable mortality, complication, and conversion rates.

Adult↗

PubMed2003

[The learning curve in the context of the cesarean section].

BACKGROUND: We created learning curves to define an objective figure according to which residents are capable of performing a cesarean section responsibly without supervision. METHODS: We established learning curves of 9 different outcome variables related to cesarean section for all trainees of obstetrics-gynecology in the years 1995-1999 (blood loss, length of stay, Apgar score, umbilical cord pH value, induction-delivery time, uterotomy-delivery time and total operation time). The change from the steep to the flat part of the curve was determined visually and defined as the end of the initial learning phase. RESULTS: 15 residents performed a total of 371 sections. Concerning the operation time and the induction-delivery time, the steep part of the curve was exceeded after 20 sections. For the 1-min Apgar score and the length of stay, only a slight change in the curve was present; for the remaining parameters, no learning process could be demonstrated. CONCLUSION: For cesarean sections of average risk, 20 procedures are adequate to provide sufficient safety for the patient.

Apgar Score↗

PubMed2004

The learning curve: implications of a quantitative analysis.

The negatively accelerated, gradually increasing learning curve is an artifact of group averaging in several commonly used basic learning paradigms (pigeon autoshaping, delay- and trace-eye-blink conditioning in the rabbit and rat, autoshaped hopper entry in the rat, plus maze performance in the rat, and water maze performance in the mouse). The learning curves for individual subjects show an abrupt, often step-like increase from the untrained level of responding to the level seen in the well trained subject. The rise is at least as abrupt as that commonly seen in psychometric functions in stimulus detection experiments. It may indicate that the appearance of conditioned behavior is mediated by an evidence-based decision process, as in stimulus detection experiments. If the appearance of conditioned behavior is taken instead to reflect the increase in an underlying associative strength, then a negligible portion of the function relating associative strength to amount of experience is behaviorally visible. Consequently, rate of learning cannot be estimated from the group-average curve; the best measure is latency to the onset of responding, determined for each subject individually.

Algorithms↗

PubMed2003

Multidimensional analysis of learning curves in laparoscopic sigmoid resection: eight-year results.

PURPOSE: The number of operations to reach a plateau phase in colorectal laparoscopic surgery is still under debate. There are few publications reporting on multidimensional assessment of the learning curve, including operation time and complication and conversion rates. The purpose of this study was to define a multidimensional learning curve for sigmoid resection performed by two surgeons with experience in laparoscopic surgery. METHODS: Between 1993 and 2001 from a total of 715 laparoscopic colorectal procedures, two surgeons performed self-educated 338 sigmoid resections. Demographic data, indications for surgery, procedure performed, operation time, frequency and kind of complications, conversion rate, and days to discharge were recorded. The moving average method was used to demonstrate the change of the operation time. The cumulative sum technique was used to chart the changes in the conversion and complication rates. RESULTS: Surgeon A performed 199 and Surgeon B 139 sigmoid resections. The operation time decreased from 225 minutes to 169 minutes after approximately 90 operations for Surgeon A and from 270 minutes to 223 minutes after 110 operations for Surgeon B. Based on a decline in intraoperative complications and conversion rate, the steady state was reached after approximately 70 to 80 interventions for both surgeons. CONCLUSIONS: The assessment of a learning curve should not be limited to measurement of a decrease in operation time but should also include the conversion and complication rates. The cumulative sum technique and moving average method as proposed in this study seem appropriate to evaluate the learning curve in this clinical domain. Our findings might be especially useful for those planning training programs in laparoscopic surgery.

Adult↗

PubMed2005

Is the learning curve for laparoscopic fundoplication determined by the teacher or the pupil?

BACKGROUND: For all surgical procedures, a surgeons' learning curve can be anticipated during which complication rates are increased. The aims of this study were to evaluate individual learning curves for a group of surgeons performing laparoscopic fundoplication and to evaluate if the Procedicus MIST-simulator (Mentice Inc., Göteborg, Sweden) accurately predicts surgical performance. METHODS: Twelve Nordic centers participated, each contributing with a "master" and a "pupil" surgeon. The pupils were tested in the simulator and thereafter performed their first 20 supervised operations. All procedures were videotaped and evaluated by 3 independent reviewers. RESULTS: A significant decrease in operative time (P <0.001) and a trend (P = 0.12) toward improved score were seen during the series. The master significantly affected the pupil's score (P =0.0137). The simulator-test showed no correlation with the operative score. CONCLUSIONS: Individual learning curves varied, and the teacher was shown to be the most important factor influencing the pupil's performance score. The correlation between assessed performance and patient outcome will be further investigated.

Computer Simulation↗

PubMed2006

Robotically assisted totally endoscopic atrial septal defect repair: insights from operative times, learning curves, and clinical outcome.

BACKGROUND: Remote access perfusion and robotics have enabled totally endoscopic closure of atrial septal defect and patent foramen ovale. The aim of this study was to address learning curve issues of totally endoscopic atrial septal defect repair on the basis of a single-center experience and to investigate whether long cardiopulmonary bypass and aortic occlusion times influence intraoperative and postoperative outcomes. METHODS: Seventeen patients (median age, 35 years; range, 16 to 55 years) underwent totally endoscopic atrial septal defect repair using remote access perfusion and robotic technology (da Vinci telemanipulation system). Learning curves were assessed by means of regression analysis with logarithmic curve fit. The effect of operative variables on clinical outcome was analyzed by linear regression using the Spearman's rho coefficient. RESULTS: No operative mortality or serious surgical complications were observed. No residual shunt was detected at intraoperative or postoperative echocardiography. Significant learning curves were noted for total operative time: y(min) = 406 - 49 ln(x) (r2 = 0.725; p = 0.002); cardiopulmonary bypass time: y(min) = 225 - 42 ln(x) (r2 = 0.699; p = 0.003); and aortic occlusion time: y(min) = 117 - 25 ln(x) (r2 = 0.517; p = 0.04), x = number of procedures. Median ventilation time, intensive care unit stay, and hospital length of stay were 7 hours (range, 2 to 19 hours), 26 hours (range, 15 to 120 hours), and 8 days (range, 5 to 14 days), respectively. No correlation was detected between cardiopulmonary bypass time and intubation time (r2 = 0.283; p = 0.326), intensive care unit stay (r2 = -0.138; p = 0.639), or total length of stay (r2 = 0.013; p = 0.962). CONCLUSIONS: Totally endoscopic atrial septal defect repair can be performed safely, and learning curves for operative times are steep. Longer cardiopulmonary bypass times had no negative impact on intraoperative and postoperative outcome.

Adolescent↗

PubMed2000

Is there a learning curve associated with the use of remifentanil?

UNLABELLED: This study prospectively determined whether there was a learning curve with the use of remifentanil, as indicated by decreased hemodynamic variability, improved recovery profile, and decreased incidence of opioid-related adverse events with increasing experience. Patients undergoing diverse surgical procedures (outpatient [n = 1340] and inpatient [n = 560]) were enrolled by investigators (n = 190) who had no previous experience with remifentanil use. Each investigator enrolled 10 patients. A standardized protocol for administration of remifentanil was used. Data were analyzed to determine differences between the first three patients and the last three patients enrolled for each anesthesiologist in the study. There were no differences in hemodynamic variables between the first triad and the last triad in either outpatients or inpatients. Requirements for hypnotic drugs and the doses of remifentanil used were also similar between groups. Analgesic medications administered at the end of surgery and in the postanesthesia care unit (PACU) were similar between groups, except that the last triad in the outpatient group received smaller doses of fentanyl compared with the first triad. Times to response to verbal command, tracheal extubation, and operating room discharge did not differ between groups. However, patients in the last triad undergoing outpatient surgery had shorter times to eligibility for PACU discharge, but times to eligibility for discharge home did not differ. The overall incidence of all adverse events (i.e., hypotension, hypertension, muscle rigidity, respiratory depression, apnea, nausea, and vomiting) was less in the last triad as compared with the first triad. When analyzed separately, only the incidence of vomiting (in the outpatient group) was decreased in the last triad as compared with the first triad. This study suggests that there is a learning curve that aids reduction of minor adverse effects associated with the use of analgesic medications administered at the end of surgery in outpatients, which might have reduced the incidence of postoperative vomiting and the duration of PACU stay. IMPLICATIONS: This study demonstrated that anesthesiologists rapidly acquire the ability to use remifentanil with limited experience. However, there is a learning curve that aids reduction of minor adverse effects associated with the use of analgesic medications administered at the end of surgery in outpatients, which might have reduced the incidence of postoperative vomiting and the duration of postanesthesia care unit stay.

Adult↗

PubMedDate not supplied

Generating a learning curve for pediatric caudal epidural blocks: an empirical evaluation of technical skills in novice and experienced anesthetists.

BACKGROUND AND OBJECTIVES: Learning curves for anesthesia procedures in adult patients have been determined, but no data are available on procedures in pediatric anesthesia. The aim of this study was to assess the number of caudal blocks needed to guarantee a high success rate in performing caudal epidural analgesia in children. METHODS: At a teaching hospital, the technical skills of 7 residents in anesthesiology who performed caudal blocks were evaluated during 4 months using a standardized self-evaluation questionnaire. At the start of the study period, the residents had no prior experience in pediatric anesthesia or in performing caudal epidural blocks. All residents entered the pediatric rotation after a minimum of 1 year of training in adult general and regional anesthesia. The blocks were rated using a binary score. For comparison, the success rates of 8 experienced staff anesthesiologists were collected during the same period using the same self-evaluation questionnaire. Statistical analyses were performed by generating individual and institutional learning curves using the pooled data. The learning curves were calculated with the aid of a least-square fit model and 95% confidence intervals were estimated by a Monte Carlo procedure with a bootstrap technique. RESULTS: The success rate of residents was 80% after 32 procedures (95% confidence interval of 0.59 to 1.00). The pooled success rate of the staff anesthesiologists was 0.73 (mean) with a standard deviation of 0.45, which was not statistically different from the success rate of the residents. CONCLUSION: High success rates in performing caudal anesthesia in pediatric patients can be acquired after a limited number of cases. Success rates of residents learning this procedure are comparable to the results of staff anesthesiologists.

Anesthesia, Caudal↗

PubMed2001

The AO distal locking aiming device: an evaluation of efficacy and learning curve.

OBJECTIVES: The AO nail mounted 'distal locking aiming device', developed to obtain radiation independent distal locking, has an unproven efficacy in a large clinical setting. This prospective study compares the efficacy and learning curve of the distal aiming device with the popular 'free hand technique'. MATERIALS AND METHODS: Distal locking in thirty cases of statically locked intramedullary femur nailing using the distal aiming device for rotationally stiff unslotted AO SUN nails was prospectively compared with the same number using the free-hand technique with regard to duration, radiation exposure, accuracy of screw placement, and learning curve. RESULTS AND DISCUSSION: For the free-hand technique and the distal aiming system respectively, the average distal locking time was 35.8+/-18.6 versus 19.3+/-9.8 minutes, and the average number of images taken to achieve distal locking was 11.5+/-3.4 versus 3.8+/-3.5. The decrease in average distal locking time by 46.1% and in radiation by 70.0% with the distal aiming system is statistically significant at P<0.001. There were three failures of the distal aiming device and these were converted to the free-hand technique. The learning curve for the distal aiming device was shorter and more predictable than that with the free hand technique. We also analyse the failures and associated pitfalls with the system. CONCLUSIONS: We found the AO distal locking aiming device to be an accurate, radiation-independent jig with a short and predictable learning curve.

Bone Nails↗

PubMed2004

Robotic totally endoscopic coronary artery bypass: program development and learning curve issues.

BACKGROUND: The introduction of new procedures in heart surgery is a critical phase that includes learning curves and the risk of increased mortality or morbidity. Totally endoscopic coronary artery bypass grafting using robotic techniques represents such an innovative procedure. The aim of this report is to demonstrate the safe introduction of totally endoscopic coronary artery bypass grafting using a stepwise and modular approach. METHODS: From June 2001 until December 2002, 50 procedures were performed using the da Vinci telemanipulator system. After baseline training the following procedure modules were carried out in a stepwise manner: robotically assisted endoscopic left internal thoracic artery harvesting and completion of the procedure as conventional coronary artery bypass grafting, minimally invasive direct coronary artery bypass, or off-pump coronary artery bypass (n = 19), robotically assisted suturing of left internal thoracic artery to left anterior descending anastomoses during conventional coronary artery bypass grafting (n = 15), totally endoscopic coronary artery bypass grafting on the arrested heart using remote access perfusion and aortic endocclusion coronary bypass grafting (n = 15). One patient was excluded intraoperatively from a robotic procedure due to pleural adhesions. RESULTS: A significant learning curve was observed for left internal thoracic artery takedown time, y(min) = 181 - 39 x ln(x) (x = procedure number) (P <.001), and total operative time in totally endoscopic coronary artery bypass grafting, y(min) = 595 - 87 x ln(x) x = (procedure number) (P =.028). The conversion rate in totally endoscopic coronary artery bypass grafting was 2/15. Intensive care unit stay correlated significantly with total operative time (r =.427, P =.002). There was no hospital mortality. CONCLUSION: Totally endoscopic coronary artery bypass grafting can be safely implemented into a heart surgery program. Learning curves are steep for robotic left internal thoracic artery takedown and for performance of totally endoscopic coronary artery bypass grafting. Long operative times translate into prolonged intensive care unit stay in specific cases but not into increased mortality.

Adult↗

PubMed2003

Long-term results and learning curve for radio frequency ablation of accessory pathways.

Radio frequency (RF) catheter ablation of accessory pathways represents an interventional method in modern cardiology that has become the first-line treatment for patients with symptomatic WPW-syndrome. The aim of this study was to analyze: (1) the learning curve for the ablation procedure; (2) procedural parameters and success; and (3) personal assessment of the treatment by the patients. Learning curve analysis included 195 consecutive patients, who underwent ablation between 1991 and 1996. The follow-up survey included 65 consecutive patients. The analysis of the procedural parameters showed significant improvement after 100 cases, implying a completion of the learning curve at this point. Long-term follow-up showed a high success rate for all pathways (95.4%). All procedure parameters indicated significantly higher degree of difficulty for right free-wall and septal pathways, with lowest long-term success rate for right-sided pathways (78.6%). Personal assessment survey showed high acceptance of the treatment; the procedure was described as a significant improvement of overall quality-of-life by 92.3% of patients. The results of this study confirm the catheter ablation of accessory pathways--in particular after completion of the learning curve--as a low-risk and highly efficient treatment for symptomatic WPW-syndrome, with a high degree of patient-related acceptance.

Adolescent↗

PubMed1996

The learning curve for totally extraperitoneal laparoscopic inguinal hernia repair.

BACKGROUND: Several laparoscopic techniques have been introduced to re pair inguinal hernia, the newest and most promising being a totally extraperitoneal approach. Nevertheless, the surgeon may encounter several complications and technical difficulties associated with the transition from the conventional anterior operation. METHODS: In late 1993 and 1994, 120 patients were operated on for inguinal hernia using the totally extraperitoneal approach by four laparoscopic surgeons inexperienced in this new technique in a secondary referral setting. Their learning curve was assessed through operation time, perioperative and postoperative complications, and technical difficulties. RESULTS: Median operative time decreased significantly (P = 0.0003) when going through the learning curve. During the initial part of the learning curve, conversion to another technique was necessary in 10 (8%) cases, and in 6 of these cases, conversion was needed for a peritoneal tear (relative risk for conversion if peritoneal tear was present: 4.0; 95% confidence interval 1.2 to 13.1, P = 0.025). The median operative time for Nyhus type IIIb and IVb hernias was significantly longer than for other types (70 versus 55 minutes, P = 0.003). Median postoperative stay was 2 days (range 0 to 7). There were 10 recurrences within 6 months due to technical or judgement errors. CONCLUSIONS: For surgeons, the learning curve for totally extraperitoneal laparoscopic hernia repair can be overcome; however, the presence of an experienced surgeon during the procedure is vital, as this may prevent unnecessary recurrences.

Adolescent↗

PubMed1998

Thoracoscopic sympathectomy for hyperhidrosis: is there a learning curve?

The aim of this study was to evaluate the learning curve of upper dorsal thoracoscopic sympathectomy. From June 1993 to December 1996, we performed 232 sympathectomies on 116 patients with primary palmar hyperhidrosis. The T2-T3 ganglia were resected by electrocuting and were removed for histologic examination. The series was divided into two groups of 58 patients each, and operations in each group occurred during a period of 21 months. Follow-up was obtained on 111 patients for a mean of 25.06+/-12.62 months. All limbs were dry after the operation, and hyperhidrosis did not recur. The anesthesia time was reduced, but the operating time, the difficulty in identifying and in resecting the ganglia, compensatory hyperhidrosis, postoperative neuralgia, and subjective satisfaction with the procedure were similar in both groups. The learning curve in the present study was mainly reflected by a reduction in the incidence of Horner's syndrome.

Adolescent↗

PubMed1993

Early experience with directional coronary atherectomy: documentation of the learning curve.

OBJECTIVE: To evaluate evolving selection criteria and angiographic outcome ('learning curve') for directional coronary atherectomy. SETTING: Tertiary referral, university-based hospital. PATIENTS: Initial 50 subjects undergoing directional coronary atherectomy of de novo left anterior descending stenoses at The Toronto Hospital from July 1990 to April 1991. INTERVENTIONS: Directional coronary atherectomy according to standard interventional techniques, with pre- and post procedure qualitative evaluation and quantitative coronary arteriography (Cardiac Measurement System; Leiden, The Netherlands) to define angiographic outcome. RESULTS: Comparing 'early' (group 1) versus 'late' (group 2) subjects, baseline demographics and clinical parameters were similar. Later subjects demonstrated increased coronary tortuosity (group 1, 1.40 versus group 2, 1.64, P < 0.01) and major side branch involvement within the stenosis (group 1, seven of 25 [28%] versus group 2, 18 of 25 [72%], P < 0.01). Regardless of experience, post procedure residual minimum stenotic diameters were equal (group 1, 2.75 +/- 0.55 versus group 2, 2.49 +/- 0.42 mm) in progressively longer lesions (group 1, 11.4 +/- 4.9 versus group 2, 13.3 +/- 5.5 mm, P < 0.1), with increased symmetry (group 1, 0.60 +/- 0.28 versus group 2, 0.73 +/- 0.19, P < 0.05). Analysis of consecutive pentiles (10 subjects per group) indicated gradual increases in post procedure residual lumen during early experience (the first 30 subjects), with an abrupt deterioration in outcome (fourth pentile), secondary to qualitative changes in coronary anatomy, before a return to satisfactory residual minimum stenotic diameters (fifth pentile). CONCLUSIONS: This study defines a distinct 'learning curve' during the initial 30 patients undergoing directional coronary atherectomy, with subtle changes in case selection, predominantly reflected by qualitative indices (eg, tortuosity, dystrophic calcification), resulting in a transient deterioration in final outcomes (patient 31 to 40). Subsequently, optimal results were re-established after defining appropriate case selection criteria, in conjunction with progressive expertise.

Adult↗

PubMed2004

[Intraoperative complications and morbidity of laparoscopic radical prostatectomy (LRP) during the learning curve].

OBJECTIVES: To analyze the complications and morbidity during our learning curve of laparoscopic radical prostatectomy (LRP) and compare them with other published series. METHODS: We review the 25 first laparoscopic radical prostatectomies performed in our department, evaluating the operative technique and other features such as surgical time, blood loss, complications and conversion to open surgery. We also evaluate morbidity, postoperative hospital stay, and functional features such as potency and continence. RESULTS: LRP was completed in 22 patients. Overall intraoperative complication rate was 32%. 3 cases were converted to open surgery due to technical difficulties or intraoperative complications. We had complications in 4 patients, that were not severe (bladder injury 2 cases, and epigastric artery injury another 2) and where solved without difficulties during the operation. The most severe intraoperative complication was related to the anesthesia procedure at the time of extubation of a patient who required tracheotomy. There were no severe postoperative complications, being leakage from the anastomosis the most common (7 cases). All of them were managed conservatively, although this resulted in a mean hospital stay of 10.8 days. 2 patients required endoscopic procedures in the immediate postoperative time for bladder catheter repositioning. All patients suffered erectile dysfunction and the continence rate at 3 months was 77.2%. CONCLUSIONS: Although LRP is a long operation and difficult during the learning curve, its complication rate is acceptable because they are not severe and can be managed in a relatively easy way.

Aged↗

PubMed2002

The construction of learning curves for basic skills in anesthetic procedures: an application for the cumulative sum method.

UNLABELLED: This study aimed at constructing learning curves for basic procedural skills in anesthesiology using the cumulative sum method. We recorded 1234 peripheral venous cannulations, 895 orotracheal intubations, 688 spinals, and 344 epidurals performed by residents during the first 10 mo of training. Learning curves for each procedure were constructed by using the cusum method. The number of procedures performed until attainment of acceptable failure rates was calculated. All residents mastered peripheral venous cannulation after 79 +/- 47 procedures. Four of 7 residents attained acceptable failure rates at orotracheal intubation after 43 +/- 33 proce- dures. Seven of 11 residents attained acceptable failure rates at spinal anesthesia after 36 +/- 20 procedures. At epidural anesthesia, 5 of 11 residents attained acceptable failure rates after 21 +/- 11 procedures. The cusum method is a useful tool for objectively measuring performance during the learning phase of basic procedures. The wide interindividual variability in the number of procedures required to be performed before attaining acceptable failure rates suggests that performance should be followed on an individual basis. IMPLICATIONS: Learning curves for peripheral venous cannulation, tracheal intubation, and spinal and epidural anesthesia were constructed using the cumulative sum (cusum) method. There was a wide variability in the number of procedures performed until attainment of acceptable failure rates. The cusum method may improve our means of evaluating residents' technical skills.

Anesthesia, Epidural↗

PubMed2005

The learning curve associated with thoracoscopic spinal instrumentation.

STUDY DESIGN: Consecutive case prospective radiographic and medical record review. OBJECTIVE: To define the learning curve associated with thoracoscopic spinal instrumentation by evaluating operative data and early outcomes of 1 surgeon's (B.L.) cases. SUMMARY OF BACKGROUND DATA: Thoracoscopic spinal instrumentation for the treatment of thoracic adolescent idiopathic scoliosis has emerged as an alternative to open anterior and posterior techniques. The technique is technically demanding and has been perceived as having a prohibitive learning curve. METHODS: The operative reports, charts, and surgeon's database were used to evaluate operating time, estimated blood loss, levels fused, complication rate, blood transfusions, and curve correction, among other variables. For purposes of analysis, the entire cohort was divided into 2 groups of 28 and 29 patients, respectively, and then 4 groups of 14 patients (the last group with 15) were used for comparison. RESULTS: The records of 57 patients were evaluated. No significant difference in estimated blood loss or number of levels fused was noted for either comparison (P = 0.46 and P = 0.66, respectively). There was no significant difference in blood transfusion requirements, with 7% in group 1 and 18% in group 2 (P = 0.35). Operating time was significantly less after 28 patients were operated on 6.2 +/- 1.3 hours versus 5.3 +/- 1.2 hours (P = 0.011). Percent curve correction was significantly better after 28 cases were performed, 54.4 +/- 17.9 in the former groups versus 65.7 +/- 10.4 in the latter half of cases (P = 0.005). Complications were evenly distributed throughout the series. No significant differences were observed between the 2 groups in terms of rate of complication (P = 0.50). No major complications, such as neurologic deficit or significant hemorrhage, were observed. CONCLUSIONS: The learning curve associated with thoracoscopic spinal instrumentation appears to be acceptable. Significant differences were noted in operating time and percent curve correction after 28 cases. The complication rates remained stable throughout the surgeon's experience.

Adolescent↗