Pelvic tilt affects superolateral coverage, but not superomedial coverage of the femoral head following periacetabular osteotomy.

BACKGROUND: Pelvic tilt is an important sagittal parameter that varies greatly among individuals. The objective of this study was to quantify the effect of pelvic tilt on femoral head coverage and range of motion in a dysplastic population following periacetabular osteotomy. METHODS: Twenty-three dysplastic hips from 19 patients (17 female, 2 male) were included in this study. Three-dimensional models were reconstructed using pre-operative CT images, and patient-specific neutral pelvic tilt was obtained on an anteroposterior X-ray. Following a simulated periacetabular osteotomy, the pelvic tilt was changed from -15° to +15°, and the effects on femoral head coverage and hip range of motion was quantified using a customized MATLAB program. FINDINGS: Pelvic tilt did not significantly affect total femoral head coverage (P > 0.2). However, a 15° anterior tilt from neutral resulted in a 17.72 ± 9.45% increase in anterolateral coverage and a 23.96 ± 7.48% decrease in posterolateral coverage (P < 0.0001), as well as an 18.2 ± 8.4° loss of internal rotation at 90° of hip flexion. Contrarily, posterior pelvic tilt led to a 26.79 ± 9.04% reduction in anterolateral coverage (P < 0.0001) and an 18.02 ± 9.57% increase in posterolateral coverage (P < 0.0001), and the maximum internal rotation increased 11.8 ± 3.7°. INTERPRETATION: While pelvic tilt did not affect total femoral head coverage, it had a significant impact on the distribution of coverage within the superolateral region of the femoral head. Anterior pelvic tilt led to increased anterolateral coverage, but also had a negative impact on hip range of motion. An optimal surgical plan should achieve adequate coverage while not significantly limiting the patient's mobility.

Pathologic Femur Fracture through Osteoid Osteoma after Radiofrequency Ablation: Case Report and Review of the Literature.

This is a case report of a 4-year-old girl who sustained a femoral shaft fracture 2 weeks after radiofrequency ablation of an osteoid osteoma. The fracture occurred after a relatively low-energy impact, jumping off the second to last step of a staircase. The pathologic fracture was successfully treated with closed reduction and spica casting, with full return to activities. Cases have been reported in the literature of femoral shaft fractures in older patients after radiofrequency ablation, but all are farther out than 2 weeks and none in patients as young as 4 years.

Incidence of meniscal injury and chondral pathology in anterior tibial spine fractures of children.

BACKGROUND: Pediatric avulsion fractures of the anterior tibial spine are injuries similar to anterior cruciate ligament injuries in adults. Sparse data exists on the association between anterior tibial spine fractures (ATSFs) and injury to the meniscus or cartilage of the knee joint in children. This research presents a retrospective review of clinical records, imaging, and operative reports to characterize the incidence of concomitant injury in cases of ATSFs in children. The purpose of this study was to better delineate the incidence of associated injuries in fractures of the anterior tibial spine in the pediatric population. METHODS: We identified 58 patients who sustained an ATSF and met inclusion criteria for this study between 1996 and 2011. The subjects were separated by the Myers and McKeever classification into type I, II, and III fractures, and each of these were subclassified by associated injury pattern. RESULTS: 59% of children with an ATSF had an associated soft tissue or other bony injury diagnosed by magnetic resonance imaging or arthroscopy. The most prevalent associated injuries were meniscal entrapment, meniscal tears, and chondral injury. We found no meniscal or chondral injury associated with type I fractures. Twenty-nine percent of type II injuries demonstrated meniscal entrapment, 33% showing meniscal tears. Seven percent demonstrated chondral injury. Forty-eight percent of type III fractures had entrapment, whereas 12% showed meniscal tears. Eight percent had a chondral injury. CONCLUSIONS: A majority (59%) of displaced ATSF had either concomitant meniscal, ligamentous, or chondral injury. This finding suggests that magnetic resonance imaging evaluation is an important aspect of the evaluation of these injuries, particularly in type II and type III patterns. To date, this study reports the largest number of patients to evaluate the specific question of concomitant injuries in ATSFs in the pediatric population. LEVEL OF EVIDENCE: Level IV.

Verification of musculoskeletal FDG-PET-CT findings performed for melanoma staging.

BACKGROUND: The purpose of this study is to establish the validity of F-18-deoxyglucose positron emission tomography-computed tomography (FDG-PET-CT) scan staging for cutaneous melanoma when a musculoskeletal image abnormality is detected. METHODS: An institutional review board (IRB)-approved prospective database was queried to identify 342 melanoma patients treated between 4/1999 and 12/2007. A total of 682 whole-body FDG-PET-CT scans performed for staging were retrospectively reviewed to identify FDG-avid lesions in the deep soft tissues/muscle, bone or joints (i.e., musculoskeletal sites). Images were correlated with follow-up patient records. RESULTS: There were 187 true-positive sites on 94 scans and 26 false-positive sites on 22 scans. The overall false-positive rate was 13.9% (26/187). The positive predictive value (PPV) of an isolated musculoskeletal FDG-avid site was 31%. The PPV was highest (100%) when findings were present in both the bone and deep soft tissues. The relative risk of an isolated FDG-avid site compared with multiple FDG-avid sites not being melanoma was 5.33 [95% confidence interval (CI) 2.85-9.94]. The relative risk of an FDG-avid site seen in the appendicular region not being melanoma was 1.78 (95% CI 0.87-3.64) that of a site seen in the axial region. CONCLUSIONS: FDG-PET-CT scanning for staging and surveillance in the extremities of patients with high-risk melanoma often creates confusing clinical scenarios. Our data suggest that a select subset of patients with isolated avid appendicular musculoskeletal scan may not have metastatic melanoma.

Meniscus status at anterior cruciate ligament reconstruction associated with radiographic signs of osteoarthritis at 5- to 10-year follow-up: a systematic review.

The development of premature osteoarthritis after anterior cruciate ligament (ACL) reconstruction is a significant cause of morbidity in young, active individuals. Meniscal injuries are frequently noted at the time of reconstruction, and the critical role of an intact meniscus in the prevention of osteoarthritis has been well documented. The purpose of this review is to evaluate the effects of meniscal status at ACL reconstruction on the subsequent development of osteoarthritis. A systematic review of the literature identified 11 studies with > or = 2 years of follow-up that compared patients' radiographic outcomes based on meniscus status at the time of ACL reconstruction. Patients undergoing partial meniscectomy at the time of ACL reconstruction were significantly more likely to develop radiographic evidence of osteoarthritis than those with normal menisci. Meniscal repair resulted in inconsistent findings. Virtually all patients who underwent complete meniscectomy at the time of ACL reconstruction had radiographic evidence of osteoarthritis at follow-up.

Eye protection in orthopaedic surgery. An in vitro study of various forms of eye protection and their effectiveness.

BACKGROUND: Conjunctival contamination from splashed debris during orthopaedic surgical procedures places surgeons at risk for communicable diseases such as human immunodeficiency virus (HIV) and hepatitis B and C. The purpose of this study was to compare the effectiveness of various types of protective eyewear in preventing conjunctival contamination. METHODS: A simulation model was constructed with use of a mannequin head in a typical position of a surgeon's head during an operation. The head was placed at an appropriate distance from the surgical field, and a femoral osteotomy was performed on a cadaver thigh. Six experimental groups were tested to determine the ability of various types of eye protection to prevent contamination of the conjunctiva: (1) modern prescription glasses, (2) standard surgical telescopic loupes, (3) hard plastic contoured glasses, (4) disposable plastic glasses, (5) a combination facemask and eye shield, and (6) no protection (control). Thirty femoral osteotomies were performed, and contamination of both the protective devices and the simulated conjunctival surfaces were recorded. RESULTS: None of the tested devices were completely effective. The modern prescription glasses and the controls both were associated with conjunctival contamination rates of 83%. The other eye protective devices were associated with significantly lower rates of overall contamination, with a rate of 50% for the loupes, 30% for the facemask and eye shield, 17% for the hard plastic glasses, and 3% for the disposable plastic glasses. CONCLUSIONS: Modern prescription glasses provided no benefit over the control in our experimental model; therefore, we do not recommend that they be used as the sole eye protection, especially during surgical procedures in which there is a high rate of debris expulsion from the wound. Readily available and disposable plastic glasses were associated with the lowest rate of conjunctival contamination (3%) and are an effective means with which to protect the orthopaedic surgeon from communicable diseases by conjunctival contamination.