A Simple and Low-cost Drilling Simulator for Training Plunging Distance Among Orthopedic Surgery Residents.

OBJECTIVE: Drilling through bone is a complex action that requires precise motor skills of an orthopedic surgeon. In order to minimize plunging and soft tissue damage, the surgeon must halt drill progression precisely following penetration of the far cortex. The purpose of this study was to create a low-cost and easy-to-use drilling simulator to train orthopedic residents in reducing the drill plunging depth. DESIGN, SETTING, PARTICIPANTS: This prospective observational study was performed in the division of orthopedic surgery of a single tertiary medical center. The participants included 13 residents and 7 orthopedic specialists. The simulator consisted of a synthetic femur bone model and ordinary modeling clay, and the training unit consisted of a disposable plastic tube (∼US$14), clamps (∼US$58), and a power drill + drill bit (standard hospital equipment). Plunging depths were measured by the simulator and compared between orthopedic specialists, the 6 "senior residents" (3+ years) and the 7 "junior residents" during a training session. Measurements were taken again 2 weeks following the training session. RESULTS: Initially, the plunging depths of the junior residents were significantly greater compared to those of the orthopedic specialists (7.00 mm vs. 5.28 mm, respectively, p < 0.038). There was no similarly significant difference between the senior residents and the orthopedic experts ([6.33 mm vs. 5.28 mm, respectively; p = 0.18). The senior residents achieved plunging depths of 5.17 mm at the end of the training session and 4.7 mm 2 weeks later compared to 7.14 mm at the end of the training session and 6 mm 2 weeks later for the junior residents. CONCLUSIONS: This study demonstrated the capability of a low-cost drilling simulator as a training model for reducing the plunging depth during the drilling of bone and soft tissue among junior and senior residents.

Rhabdomyolysis After Crawling Military Training.

INTRODUCTION: Rhabdomyolysis is a syndrome characterized by muscle necrosis followed by release of intracellular muscle contents into the circulation. Exertional rhabdomyolysis (ER) occurs in response to nonfamiliar and/or excessive, prolonged, or repetitive exercises, with eccentric characteristics. In military populations, due to the type of intense, all out physical loads, ER is a significant threat, particularly when training under heat stress. However, many other etiologies exist, and clinical presentations vary greatly. This heterogeneity may result in difficulty in prevention, diagnosis, and return-to-duty decision. The purpose of this report is to point to a new potential risk factor to an extreme muscle breakdown and ER. CASES DESCRIPTION: In this article, we describe three cases of ER in army recruits after strenuous acts of crawling over hard surfaces during an intense military selection process. The soldiers' creatine phosphokinase levels were markedly raised (44,000, 123,500, and 176,599 IU/L), but none of them developed any significant medical complication. DISCUSSION: There are two major mechanisms leading to ER: the mechanical pathway which is associated with muscle tension, and the metabolic pathway which is associated with cellular energy depletion. During this military selection process, the intensity of the exercises, and cycles of work and rest are highly controlled, and so are the timings of meals and fluids consumption. Moreover, the soldiers were all at least moderately fit and had participated in strenuous exercise events before. According to years of experience with this military selection process, under similar conditions (exercise volumes and loads) we have experienced along the years minimal medical events. At the same time, and this was the unique part in these case, all patients suffered significantly from mechanical injuries caused by crawling on hard surface which were not a part of the planned selection program. Thus, we suggest that the significant muscle breakdown in the presented cases occurred mostly due to crush injury and was not solely a result of the metabolic strain. CONCLUSION: Thus, we suggest that the extreme creatine phosphokinase levels may be attributed to a synergistic interaction between low-energy trauma, caused by crawling on hard soil and stones, and exertion. We also emphasize the fact that proper physiological support such as proper hydration may assist in prevention of ER complication such as acute renal failure.

Anchor suture fixation of distal pole fractures of patella: twenty seven cases and comparison to partial patellectomy.

PURPOSE: Partial patellectomy (PP) and reattachment of the patellar ligament with transosseous suturing is the mainstay of surgical treatment for distal pole patellar fractures. An anchor suturing (AS) technique has recently been reported as an alternative to PP in such fractures and allows for bone-to-bone interface and possibly superior fracture healing than bone-to-tendon interface with PP. We present our experience with AS and compare it to PP. METHODS: Between 2006 and 2011, 60 patients with distal pole patellar fracture underwent either AS (n = 27) or PP (n = 33). We retrospectively gathered their demographic data and information on fracture type, fixation technique, operation time, postoperative complications and knee range of motion. A telephone survey was performed to grade functional outcomes with standard questionnaires (the SF-12 for quality of life, the Kujala score for patellofemoral function and a visual analog scale [VAS] pain score). RESULTS: AS was equivalent to PP in terms of residual pain and functional outcomes (VAS: 2.45 vs. 2.26, p = 0.83 and Kujala score: 74.3 vs. 69, p = 0.351, respectively) as well as for knee range of motion. Complications included three cases of infection in each group, two cases of early hardware failure and one case of non-union in the AS group. Operation time was significantly shorter for AS compared to PP (68.5 vs. 79.1 min, p = 0.03). CONCLUSIONS: AS is non-inferior to PP for function and pain after distal pole patellar fractures and is superior to PP with regard to operative time. Common complications of this technique are hardware failure and infections. LEVEL OF EVIDENCE: Therapeutic Level III.

Predictors for nonunion, reoperation and infection after surgical fixation of patellar fracture.

INTRODUCTION: The most common major complications following surgical fixation of patellar fractures are infection, nonunion and reoperation. In this study, we sought to define the predisposing factors to the development of these complications. METHODS: Open reduction and internal fixation surgeries for patellar fractures that were performed in a single institution between 2006 and 2011 were retrospectively reviewed. Patients' demographic data (age, gender, comorbidities), injury and fracture data (associated injuries, type of fracture, open or closed fracture), surgical data (type of surgery and interval between fracture occurrence and surgery) and major postoperative complications (infection, nonunion, symptomatic hardware and revision surgery) were collected from the medical records and verified by a telephone survey. Correlation analysis identified the major variables influencing the development of these complications. RESULTS: The cohort of 188 patients had an average follow-up of 908 days. Thirteen (6.9 %) patients developed infection, 3 (1.6 %) had fracture nonunion and 42 (22.3 %) required a second operation. A history of cerebrovascular accident (CVA) correlated significantly with the development of infection (OR 6.18, CI 1.1-35.6, p = 0.041) and nonunion (OR 14.9, CI 1.2-188.1; p = 0.037). A history of diabetes significantly increased the risk of a second operation (OR 8.69, CI 95 % 1.8-41.9, p = 0.007). Open fracture did not increase the risk of any of these complications. CONCLUSIONS: A history of CVA and diabetes mellitus significantly increased the risk of complications following patellar fracture fixation. Patients with these comorbidities should be informed of their increased risk of these complications and be followed up more rigorously.

The incidence of heterotopic ossification in hip arthroscopy.

PURPOSE: The purpose of this study was to assess the incidence of heterotopic ossification (HO) after hip arthroscopy. METHODS: Between July 2010 and July 2011, 83 patients underwent hip arthroscopy for various etiologies. We prospectively reviewed 50 consecutive hip arthroscopy procedures (31 male and 19 female patients; mean age, 36.7 years) with a mean follow-up of 29.56 weeks (range, 9 to 62 weeks) to assess the incidence of HO and its effect on function and clinical outcome. Preoperative and postoperative evaluation included general assessment by visual analog scoring, modified Harris Hip Score, Hip Outcome Score, and preoperative and postoperative radiographs. Heterotopic bone formation was assessed on radiographs at a minimum of 9 weeks from surgery with the Brooker classification. RESULTS: Of the patients, 22 (44%) had radiographic evidence of postoperative HO (15 male patients): 13 (26%) had Brooker stage 1, 5 (10%) had Brooker stage 2, and 4 (8%) had Brooker stage 3. HO appeared as early as 9 weeks after surgery. No significant difference was found in demographic data, surgery-related data, or clinical and functional scores between patients with HO and patients without HO. No factor was found to significantly affect the incidence of HO after logistic regression. No distinct clinical manifestation was associated with the presence of HO. CONCLUSIONS: This study shows that the incidence of HO after hip arthroscopy may be underestimated. We could not find a contributing factor to the formation of HO. Although in most cases the presence of HO will have minimal or no clinical and functional significance, it should be sought at a minimum of 9 weeks postoperatively. LEVEL OF EVIDENCE: Level IV, therapeutic case series.