Reliability of measurements of clavicle shaft fracture shortening in adolescents.

BACKGROUND: A relative indication for surgical treatment of midshaft clavicle fractures is shortening ≥2.0 cm. A standard method for determining shortening with routine clavicle radiographs has not been established. This study evaluated the interobserver and intraobserver reliability when measuring shortening of midshaft clavicle fractures in adolescents. METHODS: We identified all clavicle radiographs of simple midshaft clavicle fractures in adolescents from 2006 to 2010. Thirty-two radiographs were chosen following a power analysis for 7 observers. Each film was measured twice by each evaluator using 2 separate methods. Method 1 was the evaluator's method of choice to determine shortening on the digital radiographs. Method 2 was standardized. Intraclass correlation coefficient and confidence intervals (CI) were calculated to determine interrater reliability, and average differences between the 2 time points with 95% CI were calculated to determine intrarater reliability. RESULTS: Interrater reliability for method 1 was 0.771 (95% CI, 0.655-0.865) and 0.743 (95% CI, 0.604-0.851) at the 2 time points for fair agreement. Interrater reliability for method 2 was 0.741 (95% CI, 0.629-0.842) and 0.685 (95% CI, 0.554-0.805) at the 2 time points, for fair and poor agreement, respectively. Neither method was statistically superior to the other. For method 1, the SD for the measurements averaged 3.1 mm. For method 2, the average SD was 3.0 mm. Intrarater reliability for method 1 was 2.62 mm average difference between the 2 time points (95% CI, 2.24-3.00), and for method 2 it was 3.34 mm average (95% CI, 2.88-3.80). Method 2 had a significantly greater difference at the 2 time points than method 1 (P=0.027). CONCLUSIONS: There is only fair agreement among observers when measuring the shortening of clavicle fractures in adolescents on digital clavicle radiographs by either method described. However, as the average difference among measurers was only 3 mm, this is unlikely to influence clinical decision making. A lack of standardization of measurement in previous studies on clavicle fracture treatment may not represent a significant problem. LEVEL OF EVIDENCE: Level III diagnostic study.

Combined Tillaux and Bimalleolar Ankle Fracture in a Pediatric Patient: A Case Report.

Adolescents are at risk of unique ankle fracture patterns due to closing physes. Transitional ankle fractures, in particular, are an entity specific to adolescent patients due to the asymmetrically open distal tibia physis. Transitional ankle fractures are rarely seen in combination with bimalleolar ankle fracture patterns. This case is of interest because the combined fracture pattern and the treatment method presented have not been previously reported in the literature to our knowledge. A 15-year-old female presented with right ankle pain after a fall while roller skating. Imaging demonstrated a right Tillaux fracture with ipsilateral displaced medial malleolus fracture and minimally displaced Weber C distal fibula fracture. The Tillaux fracture and medial malleolus fractures were treated with open reduction and internal fixation with partially threaded compression screws. The lateral malleolus remained minimally displaced and did not require operative fixation. The patient healed well with no complications. Transitional injuries of the ankle in adolescents have been reported in the literature; however, combined injuries are uncommon and lack representation in the current literature base. These combined injuries are important to be aware of, as missed injuries can result in long-term pain and disability.

Ossifying lipoma of c1-c2 in an adolescent.

BACKGROUND: Ossifying lipomas, characterized by their independence of bony connection to the skeleton, are extremely rare benign neoplasms. They have primarily been described in adults older than 50 years of age and occur in the head and neck region. The etiology is unknown. Excision is the preferred treatment. The objective of this study is to report the case of a rare ossifying lipoma immediately anterior to C1 to C2, requiring a transoral approach for excision. METHODS: The case of an adolescent with a retropharyngeal mass is described. RESULTS: A 15-year-old female patient presented with an asymptomatic parapharyngeal mass detected on routine physical examination. Computed tomography and magnetic resonance imaging noted a calcified, left-sided, parapharyngeal mass, approximately 3×2×2 cm, anterior to C1 and C2, most consistent with a benign osseous lesion. A transoral approach was used to excise the mass. Histologic examination demonstrated an ossifying lipoma. Postoperative imaging confirmed complete excision. The postoperative course was unremarkable, and the patient has had no recurrence at 6-month follow-up. CONCLUSIONS: This case demonstrates that a transoral approach to a lesion anterior to C1 to C2 in an adolescent can be safe, complete, and effective. LEVEL OF EVIDENCE: Case Report, level 5.

Pelvic Avulsion Injuries in the Adolescent Athlete.

Pelvic avulsion fractures are common in youth athletes; many of these injuries can be treated conservatively. This article reviews the etiology, presentation, and management of the more common pelvic avulsion fractures, including anterior superior iliac spine, anterior inferior iliac spine, ischial tuberosity, and iliac crest avulsions. Adolescent pelvic avulsion fractures rely on the amount of fracture displacement to guide treatment. Conservative management includes rest and avoiding use of the muscle(s) that attach to the avulsed fragment. Operative treatment is reserved for widely displaced fractures or symptomatic nonunions. With appropriate treatment, young athletes frequently return to their same level of sport.

How accurately do novice surgeons place thoracic pedicle screws with the free hand technique?

STUDY DESIGN: Cadaver study. OBJECTIVE: To evaluate with direct observation the errors made when novice resident surgeons place thoracic pedicle screws. To determine how many specimens need to be instrumented to assure an improvement in accuracy to currently published levels. SUMMARY OF BACKGROUND DATA: Thoracic pedicle screw instrumentation has been shown to provide numerous benefits in spinal deformity surgery including 3 column fixation of the spinal elements, decreased need for thoracoplasty or anterior thoracic release and decreased operative time and blood loss. METHODS: Three orthopaedic residents inexperienced in pedicle screw placement received an introductory teaching session. Intact thoracic vertebral body specimens were harvested from 15 cadaver spines. Each vertebral body was mounted on a clear Plexiglas frame with only the posterior surface anatomy visible to the surgeon. Each resident surgeon instrumented 5 thoracic spines verbalizing all perceived pedicle wall violations as they occurred. An observer recorded the accuracy of the gearshift probe, flexible probe, tap, and screw placement. Critically perforated screws were defined as a greater than 2 mm breach of the pedicle wall. RESULTS: Two hundred ninety-seven pedicles in 149 intact vertebral body specimens were instrumented. Eighty-five (29%) screws were not fully within the pedicle. Sixty-three (74%) were noncritical violations and 22 (26%) were critical violations. There were 18 (21%) screw violations not perceived by the surgeon to be outside the pedicle. There was a decrease in the proportion of total screw violations by the third cadaver (P < 0.001) and in critical screw violations by the fourth cadaver (P = 0.01). CONCLUSION: Novice resident surgeons placing thoracic pedicle screws in cadavers were able to significantly improve by the fourth cadaver to accuracy levels documented in the literature. Surgeons in training shouldpractice these skills in the laboratory before proceeding to the operating room.

Role of PTEN and Akt in the regulation of growth and apoptosis in human osteoblastic cells.

Cancer cells are characterized by either an increased ability to proliferate or a diminished capacity to undergo programmed cell death. PTEN is instrumental in regulating the balance between growth and death in several cell types and has been described as a tumor suppressor. The chromosome arm on which PTEN is located is deleted in a subset of human osteosarcoma tumors. Therefore, we predicted that the loss of PTEN expression was contributing to increased Akt activation and the subsequent growth and survival of osteosarcoma tumor cells. Immunoblot analyses of several human osteosarcoma cell lines and normal osteoblasts revealed relatively abundant levels of PTEN. Furthermore, stimulation of cell growth or induction of apoptosis in osteosarcoma cells failed to affect PTEN expression or activity. Therefore, routine regulation of osteosarcoma cell growth and survival appears to be independent of changes in PTEN. Subsequently, the activation of a downstream target of PTEN activity, the survival factor Akt, was analyzed. Inappropriate activation of Akt could bypass the negative regulation by PTEN. Analyses of Akt expression in several osteosarcoma cell lines and normal osteoblasts revealed uniformly low basal levels of phosphorylated Akt. The levels of phosphorylated Akt did not increase following growth stimulation. In addition, osteosarcoma cell growth was unaffected by inhibitors of phosphatidylinositol-3 kinase, an upstream activator of the Akt signaling pathway. These data further suggest that the Akt pathway is not the predominant signaling cascade required for osteoblastic growth. However, inhibition of PTEN activity resulted in increased levels of Akt phosphorylation and enhanced cell proliferation. These data suggest that while abundant levels of PTEN normally maintain Akt in an inactive form in osteoblastic cells, the Akt signaling pathway is intact and functional.