An Update on Pediatric Acute Hematogenous Osteomyelitis in New Zealand - A Decade on.

INTRODUCTION: New Zealand (NZ) has high rates of pediatric acute hematogenous osteomyelitis (AHO) with males and children of Pasifika and Maori ethnicity overrepresented. AIMS: To update the incidence of Pediatric AHO over 10 years, identifying trends in presentation, organisms, treatment, and outcomes. METHODS: A 10-year retrospective review of children aged 6 weeks to 15 years admitted with Pediatric AHO across two centers from 2008 to 2017. Demographic data, features of presentation, investigations, management, and complications were collected. Incidence was calculated from census data. Data were compared with our osteomyelitis database from the previous decade. (1). RESULTS: 796 cases were identified. The incidence was 18 per 100,000 per annum. The average age was 7.7 years. Pasifika and Maori children are overrepresented (57%). 370 children (51%) came from low socioeconomic areas. Methicillin-sensitive Staphylococcus aureus was the most common pathogen (87%). Methicillin-resistant Staphylococcus aureus (MRSA) rates are low (4.4%). Forty-four (5.5%) children were admitted to the Pediatric Intensive Care Unit (PICU) with 9% mortality. The mean duration of antibiotics was 40 days. 325 children (41%) had surgery. Chronic infection has increased from 1.7% to 5.7%. CONCLUSIONS: NZ has high rates of AHO, however, the incidence has decreased from the previous decade. Males, those in low socioeconomic areas, Pasifika and Maori have high disease burden. The use of MRI as a diagnostic modality has increased. Future studies should focus on improving treatment via prospective analysis and reporting long-term morbidity to improve outcomes for children with severe disease and reduce rates of chronic infection.

Reverse shoulder arthroplasty compared with hemiarthroplasty in the treatment of acute proximal humeral fractures.

BACKGROUND: Complex proximal humeral fractures may require prosthetic replacement of the humeral head. Surgical options include reverse shoulder arthroplasty (RSA) and shoulder hemiarthroplasty; however, the optimal technique remains controversial. The goal of this study was to compare functional outcomes and revision rates of RSA with hemiarthroplasty in patients with acute proximal humeral fractures. MATERIALS AND METHODS: Between January 1, 1999, and December 31, 2014, there were 218 patients who underwent RSA and 427 who underwent hemiarthroplasty for acute proximal humeral fractures identified through New Zealand Joint Registry records. Study groups were compared with regard to baseline characteristics, operative characteristics, and postoperative outcomes (Oxford Shoulder Score [OSS], revision rate, mortality rate) at 6 months and 5 years after surgery. RESULTS: RSA patients were significantly older (mean age, 78.2 vs. 71.6 years; P < .001), with a higher proportion of female patients (90% vs. 77%; P < .001) than in the hemiarthroplasty group. No statistically significant difference existed in revision rate per 100 component-years (0.58 [RSA] vs. 1.16 [hemiarthroplasty]; P = .137) or 1-year mortality (3.8% vs. 3.4%; P = .805) between both groups. There was no significant difference in 6-month OSS (29.6 vs. 28.4; P = .305). The RSA group demonstrated a superior mean 5-year OSS (37.6 vs. 32.7; P = .078); however, the difference did not achieve statistical significance. CONCLUSIONS: Although our results suggest that RSA patients may experience superior 5-year functional scores, we have identified no significant difference in functional outcomes and revision rates between RSA and hemiarthroplasty in the treatment of acute proximal humeral fractures.

Femoral Neck Stress Fractures in Children Younger Than 10 Years of Age.

BACKGROUND: Femoral neck stress fractures are rare in healthy children, with only 9 cases previously reported. The present article reviews our institutional experience with femoral neck stress fractures in children younger than 10 years of age, to highlight the unique features of this condition. METHODS: We undertook a retrospective review of clinical records of patients who had been treated at our institution for an idiopathic femoral neck stress fracture between 2000 and 2014. To focus on children rather than adolescents, the World Health Organization's definition of adolescent as a person between 10 and 19 years of age was used; we thereby limited our analysis to patients younger than 10 years of age. RESULTS: The study included 6 patients (3 males, 3 females) treated for an idiopathic femoral neck stress fracture, with a mean age at diagnosis of 7.7 years (range, 5.2 to 8.9 y). All patients presented with a limp, which worsened with activity and had persisted for a mean of 5 weeks (range, 2 to 9 wk). None of the patients had experienced an increase in activity level or sporting volume before symptom onset. On examination, 3 patients experienced pain with terminal hip flexion and 3 patients demonstrated pain-free hip range of motion. Plain radiography demonstrated inferior femoral neck cortical disruption, suggesting a compression-type stress fracture mechanism. The diagnosis was confirmed by cross-sectional imaging in all cases. All patients were initially treated with 6 to 8 weeks of non-weight-bearing followed by 4 to 6 weeks of partial weight-bearing, leading to complete healing in 4 patients. Two patients demonstrated incomplete healing and were managed with spica casting for an additional 6 weeks. CONCLUSIONS: Our case series illustrates the unique features of this rare condition in children, with a history and examination profile distinct from those of adolescents and adults. Compliance with weight-bearing restrictions is difficult in this population and hip spica casting may be required to permit complete healing. LEVEL OF EVIDENCE: Level IV-case series.

Functional Movement Competency and Dynamic Balance After Anterior Cruciate Ligament Reconstruction in Adolescent Patients.

BACKGROUND: Adolescent patients undergoing anterior cruciate ligament (ACL) reconstruction may not adequately recover safe movement patterns before returning to sport participation. The aims of this study were to assess functional movement and dynamic balance 9 months after primary ACL reconstruction in adolescent patients, and to assess for any maturity-specific differences that may guide rehabilitation strategies. METHODS: A series of 39 adolescent patients who underwent primary, anatomic, transphyseal ACL reconstruction using hamstrings autograft from October 2009 to January 2013 were identified from a research database: 17 skeletally immature (SI) patients (mean age 13.6±1.6 y) and 22 skeletally mature (SM) patients (mean age 16.6±1.2 y). An adult reference population of 16 primary ACL reconstruction patients (mean age 27.4±4.0 y) was also identified. All patients followed a standardized operative and rehabilitation protocol. The 3 patient groups were compared 9 months postoperatively using the Functional Movement Screen (FMS) to assess movement competency and the Lower Quarter Y-Balance Test (LQYBT) to assess single-limb dynamic balance. RESULTS: Nine months postoperatively, the FMS scores for all 3 groups indicated an increased risk for lower extremity injury (total score ≤14). With respect to specific movement patterns, the SI group displayed inferior active straight leg raise score (P=0.006) despite a lower incidence of pain with this movement. With the LQYBT, there was no significant difference in mean anterior (P=0.987), posterolateral (P=0.349), or posteromedial (P=0.870) reach asymmetry between the 3 groups; however, the adolescent groups demonstrated wider ranges of anterior reach asymmetry than the adult group indicating an increased risk for injury. CONCLUSIONS: Adolescent patients undergoing primary ACL reconstruction do not consistently recover adequate functional movement patterns by 9 months postoperatively to permit a safe return to sport. We have identified unique functional movement deficits in SI and SM adolescents, which highlight the need for maturity-specific rehabilitation strategies for adolescent patients undergoing ACL reconstruction. LEVEL OF EVIDENCE: Level IV­retrospective cohort

Surgical Reconstruction of Metatarsal Type Preaxial Polydactyly Using an Amalgamating Osteotomy.

BACKGROUND: Polydactyly of the foot is a relatively common condition. Approximately 15% of cases are preaxial, with one third of these cases involving duplication of the metatarsal [metatarsal type preaxial polydactyly (MTPP)].Surgical reconstruction of polydactyly is indicated to improve shoe tolerance. Reconstruction of MTPP has traditionally involved resection of the hypoplastic lateral ray in addition to soft tissue reconstruction to correct hallux varus. Poor postoperative results have frequently been reported, primarily due to residual hallux varus. We present a novel surgical technique for the treatment of children with MTPP presenting with a cosmetic lateral hallux, involving an amalgamating osteotomy that permits retention of the stable medial metatarsotarsal joint while avoiding the complication of residual hallux varus. METHODS: This was a retrospective case series describing the surgical technique of an amalgamating osteotomy in the treatment of patients with MTPP and a cosmetic lateral hallux. The surgical technique involves corresponding metatarsal osteotomies of the medial and lateral halluces, with amalgamation of the metatarsals and ablation of the residual medial hallux, without the need for extensive soft tissue reconstruction. Clinical and radiologic outcomes were evaluated at a minimum of 2 years postoperatively in 2 patients who underwent this technique. RESULTS: Two children, 1 female and 1 male, underwent an amalgamating osteotomy at the age of 31 and 18 months, respectively. At latest follow-up, 7.3 and 2.8 years after osteotomy, respectively, both patients displayed an excellent functional result according to the Phelps and Grogan clinical outcome scale. Plain radiographs in both cases demonstrated a well-aligned first ray with no growth abnormality and no hallux varus. CONCLUSIONS: We have presented a novel surgical technique for the reconstruction of MTPP presenting with a cosmetic lateral hallux, involving an amalgamating osteotomy without extensive soft tissue reconstruction. This simple technique maintains the stable medial metatarsotarsal joint, permits ongoing longitudinal metatarsal growth, and avoids the complication of hallux varus. LEVEL OF EVIDENCE: Level IV-case series.

Septic arthritis and acute rheumatic fever in children: the diagnostic value of serological inflammatory markers.

INTRODUCTION: Joint pain and raised inflammatory markers are features of both acute rheumatic fever (ARF) and septic arthritis, often posing a diagnostic challenge to clinicians. Important differences in the presenting serological inflammatory marker profile may assist patient diagnosis, however, as clinical experience suggests that ARF is associated with a higher erythrocyte sedimentation rate (ESR), whereas other serological markers may be similarly elevated in these 2 conditions. OBJECTIVE: The goal of this study was to determine the diagnostic value of serological inflammatory markers and white cell count (WCC) in children presenting with acute joint pain secondary to ARF or septic arthritis. METHODS: Data were obtained from the Auckland regional rheumatic fever database and hospital computer records between 2005 and 2012. Records of all patients under the age of 16 years who were admitted with a new diagnosis of ARF or septic arthritis were analyzed. The diagnosis of ARF was defined on the basis of the New Zealand modification of the Jones Criteria, and the diagnosis of septic arthritis was defined on the basis of joint fluid cytology and culture. Baseline characteristics, serological inflammatory markers, and serum WCC were compared between the ARF and septic arthritis patient groups. RESULTS: Children with ARF displayed significantly higher ESR, higher serum C-reactive protein, and lower serum WCC than children with septic arthritis on presentation to hospital. In children presenting with monoarthritis, an ESR>64.5, serum WCC<12.1×109/L, and age above 8.5 years were found to be significant independent predictors of ARF. Children with all 3 predictors had a 71% risk for ARF and a 29% risk for septic arthritis. A significant proportion (30%) of children with the final diagnosis of ARF initially presented with monoarthritis; 14% of these children (5/34) had received nonsteroidal anti-inflammatory medication before hospital presentation, and 74% of these children (25/34) had abnormal echocardiograms on admission. CONCLUSIONS: ARF and septic arthritis are important diagnoses to consider in children presenting with acute joint pain in New Zealand. A significant proportion of patients with ARF initially present with acute monoarthritis. Serological inflammatory markers and WCC on presentation differ significantly between children with ARF and septic arthritis.

Hip dysplasia hiding in plain sight: A retrospective analysis of radiology reports.

INTRODUCTION: Timely recognition of dysplastic hip morphology is critical to facilitate appropriate management before significant joint damage has developed. It is likely that radiologist under reporting contributes to delays in diagnosis. This study aimed to assess how often adult hip dysplasia goes undetected in radiological reports and to identify clinical and radiological variables that impact the likelihood of detection of dysplasia by radiologists. METHODS: Referral details and radiology reports of patients who underwent periacetabular osteotomy by a single surgeon for symptomatic hip dysplasia between 1 January 2016 and 30 June 2020 were reviewed. Four assessors measured the lateral centre edge angle from the pelvic radiograph performed at time of referral. Film quality and other radiographic parameters were also assessed. RESULTS: Sixty-eight patients were included, 84% were female and the median age was 28.1 years. Dysplasia was not documented in the radiology report in 49% of cases. Dysplasia was more likely to be reported with no history of injury, an aspherical femoral head, lower lateral centre edge angle, higher acetabular index, increased femoral head shaft angle, higher femoro-epiphyseal acetabular roof index, or if there was disruption of Shenton's line, with the first three variables being independent predictors of radiologist detection. CONCLUSION: Hip dysplasia should be considered in all adolescents/young adults presenting with hip pain. Causes of radiologist under reporting are likely multifactorial. Clinical information can cause cognitive biases and result in selective looking. A systematic approach to pelvis radiographs should include assessment of acetabular coverage and active search for evidence of femoral head migration.

Functional outcomes of reverse shoulder arthroplasty compared with hemiarthroplasty for acute proximal humeral fractures.

BACKGROUND: Complex acute proximal humeral fractures may require prosthetic replacement of the proximal humerus. Reverse shoulder arthroplasty (RSA) has been suggested as an alternative to hemiarthroplasty in the management of such fractures. This study compared the functional outcomes of RSA with hemiarthroplasty in patients with acute proximal humeral fractures. MATERIALS AND METHODS: All patients who underwent RSA or shoulder hemiarthroplasty for acute proximal humeral fractures between January 1, 1999, and December 31, 2010 were identified from The New Zealand Joint Registry. Baseline information, operative characteristics, and postoperative outcomes (Oxford Shoulder Score [OSS] at 6 months and 5 years, revision rate, and mortality rate) were examined and compared between the study groups. RESULTS: During the study period, 55 patients underwent RSA and 313 underwent shoulder hemiarthroplasty for acute proximal humeral fractures. Compared with hemiarthroplasty patients, RSA patients were significantly older (mean age, 79.6 vs 71.9 years; P < .001) and more often women (93% vs 78%, P = .013). The 6-month OSS was 28.1 for RSA and 27.9 for hemiarthroplasty, which was not significantly different (P = .923); however, the RSA group had a significantly better 5-year OSS than the hemiarthroplasty group (41.5 vs 32.3; P = .022). There was no significant difference between the RSA and hemiarthroplasty groups in revision rate per 100 component-years (1.7 vs 1.1; P = .747) or in 1-year mortality (3.5% vs 3.6%; P > .99). CONCLUSIONS: Patients with acute proximal humeral fractures who undergo RSA appear to achieve superior 5-year functional outcomes compared with patients who undergo hemiarthroplasty.

The superomedial bare area of the costal scapula surface: a possible cause of snapping scapula syndrome.

PURPOSE: Scapulothoracic bursitis is a painful condition of the scapulothoracic articulation, which may be caused by various pathological anatomical associations. We have arthroscopically observed a constant bare area of bone on the costal scapula surface in patients with scapulothoracic bursitis, contradictory to traditional anatomical reports of scapular muscle relations. We undertook a cadaveric study to further define this anatomical feature. METHODS: Twelve cadaveric shoulders were dissected. The costal surface of the scapula was systematically examined for the presence of a superomedial bare area in each shoulder by three independent clinicians, with dimensions measured using digital calipers. RESULTS: In all shoulders, there was a clearly defined bare area of bone on the superomedial aspect of the costal surface of the scapula between the serratus anterior insertion and subscapularis origin. The bare area was typically crescenteric in shape, with variable length (mean 22.3 ± 6.0 mm) and width (10.8 ± 2.8 mm). The bare area length (p = 0.043) and width (p = 0.033) were significantly greater in female shoulders compared to male shoulders. CONCLUSIONS: We have established the presence of the superomedial bare area of the costal scapula surface. With an absence of overlying subscapularis muscle, this bare area carries the potential for scapulothoracic impingement, and should be considered as a possible aetiological factor in all patients presenting with scapulothoracic bursitis.

Outcomes of reverse shoulder arthroplasty in patients under 55 years old: Results from the New Zealand joint registry.

Background: The appropriate age at which to perform reverse shoulder arthroplasty is controversial. The aim of this study was to compare the outcomes of reverse shoulder arthroplasty between younger and older patients. Methods: Patients who underwent primary reverse shoulder arthroplasty between January 2000 and December 2019 were identified from New Zealand Joint Registry records. Patients were stratified into two cohorts according to age at the time of surgery: < 55 years and ≥ 55 years. These two groups were then compared with regard to baseline characteristics, indications for surgery, revision rates, and patient-reported outcomes using the Oxford Shoulder Score and American Shoulder and Elbow Score (ASES). Results: A total of 5518 primary reverse shoulder arthroplasty cases were identified, with 75 patients < 55 years at the time of surgery (range: 34-54 years). The mean duration of follow-up was 2.36 years (range: 0.11-13.37 years) in the younger cohort and 3.10 years (range: 0.01-16.22 years) in the older patient cohort. Indications for surgery differed significantly between the two groups, with younger patients having higher rates of inflammatory arthritis (p < 0.001), posttraumatic arthritis (p < 0.001), and avascular necrosis (p = 0.049). The younger cohort had an inferior 6-month postoperative Oxford Shoulder Score compared to the older cohort (mean: 28.5 [younger cohort] vs. 35.7 [older cohort]; p < 0.001). There was no significant difference in revision rate between the younger and older patient cohorts during the study period (1.56 [<55 years] vs. 0.74 [≥55 years] revisions per 100 component-years; p = 0.332). Conclusion: Our early results suggest that younger patients undergoing reverse shoulder arthroplasty demonstrate high implant retention rates, comparable to older patients. Longer-term patient-reported outcomes in younger patients are required to guide appropriate patient selection for reverse shoulder arthroplasty. Level of evidence: Level III, retrospective case-control study.

Early results of total hip arthroplasty in patients with slipped upper femoral epiphysis compared with patients with osteoarthritis.

We have investigated the results of primary total hip arthroplasty (THA) performed in patients with slipped upper femoral epiphysis (SUFE). Through the New Zealand Joint Registry, we identified all patients with SUFE undergoing primary THA (n = 117) and all patients with primary osteoarthritis (OA) undergoing primary THA (n = 40 589) between January 1, 1999, and December 31, 2008. Baseline information, operative characteristics, and postoperative outcomes were analyzed and compared between the SUFE and the OA groups. There was no significant difference in postoperative Oxford Hip Score or revision rate between the 2 groups. Our results support THA as a successful surgical option in the management of degenerative arthritis in SUFE, with comparable functional outcomes and revision rates to THA performed for primary OA.

Early results of total hip arthroplasty in patients with developmental dysplasia of the hip compared with patients with osteoarthritis.

We have investigated the results of primary total hip arthroplasty (THA) performed in patients with developmental dysplasia of the hip (DDH). Through the New Zealand Joint Registry, we identified all patients with DDH undergoing primary THA (n = 1205) and all patients with primary osteoarthritis (OA) undergoing primary THA (n = 40 589) between January 1, 1999, and December 31, 2008. Postoperative outcomes, baseline information, and operative characteristics were analyzed and compared between the DDH and the OA groups. There was no significant difference in Oxford Hip Score or revision rate between the 2 groups. Our results support THA as a successful surgical option in the management of degenerative arthritis in DDH, with comparable functional outcomes and revision rates to THA performed for primary OA.

Intraoperative cell salvage use reduces the rate of perioperative allogenic blood transfusion in patients undergoing periacetabular osteotomy.

Blood loss during periacetabular osteotomy (PAO) is variable, with losses ranging from 100 to 3900 ml in published series. Perioperative allogenic blood transfusion is frequently utilized although is associated with significant risk of morbidity. Cell salvage (CS) is a common blood conservation tool; however, evidence supporting its use with PAO is lacking. Our aim was to assess whether CS affects perioperative allogenic blood transfusion rate in patients undergoing PAO. The clinical records of 58 consecutive PAOs in 54 patients (median age 24.7 years, interquartile range 17.8-29.4 years) performed by a single surgeon between 1 January 2016 and 30 April 2018 were reviewed. Autologous blood pre-donation and surgical drains were not used. Due to variable technician availability, CS was intermittently used during the study period. PAOs were allocated into a CS group or no cell salvage group (NCS group), according to whether an intraoperative CS system was used. There was no significant difference in patient age, gender, body mass index, dysplasia severity, regional anesthetic technique, tranexamic acid administration, surgical duration or estimated blood loss (all P > 0.05) between the two groups. The CS group had a lower preoperative hemoglobin compared to the NCS group (median, 13.4 g/dl versus 14.4 g/dl, P = 0.006). The incidence of allogenic blood transfusion was significantly lower in the CS group compared to the NCS group (2.5% versus 33.3% patients transfused, P = 0.003). Multivariate modeling showed CS use to be protective against allogenic blood transfusion (P = 0.003), with an associated 80-fold reduction in the odds of transfusion (odds ratio, 0.01; 95th% CI, 0-0.57). To our knowledge, this is the first study to assess the effect of CS use on allogenic transfusion rate in patients undergoing PAO. Our results demonstrate CS to be a mandatory component of blood conservation for all patients undergoing PAO.

A case of Gorham's disease complicated by bilateral chylothorax.

Gorham's disease is a very rare disorder of uncertain aetiology, characterised by non-neoplastic proliferation of vascular or lymphatic channels within bone leading to resorption and replacement of osseous matrix with angiomatous tissue. Fewer than 200 cases have been reported in the literature. The complication of chylothorax is associated with a high morbidity and mortality. We present the case of a 17-year-old male with Gorham's disease of the sternum, clavicle and rib, complicated by bilateral chylothorax. Despite thoracic duct ligation and radiotherapy, the patient progressively deteriorated and died 36 weeks following initial presentation.

Do young female dancers improve symptoms and return to dancing after periacetabular osteotomy for the treatment of symptomatic hip dysplasia?

Although preservation of high activity level has been reported in active young patients after periacetabular osteotomy (PAO) for the treatment of symptomatic hip dysplasia, there is limited evidence whether a dancer may be able to resume dancing after PAO. We asked whether female dancers experience improvement in pain and sports-related activities and return to dance following PAO. Between 1997 and 2014 we performed a total of 44 PAOs in 33 female dancers with symptomatic hip dysplasia. The mean age was 20.3 years (SD 5.6 years) and the median follow-up was 2.7 years (IQR 1.7-5.9 years). The Hip Disability and Osteoarthritis Outcome Score (HOOS), the modified Harris hip score (MHHS) and hip motion were collected preoperatively and at most recent follow-up. Return to dance was recorded from self-reported questionnaires and medical record review. Female dancers reported an improvement in HOOS total scores of nearly 20 points (P = 0.007) and MHHS improved over 17 points (P = 0.01) from preoperative to most-recent follow-up. Out of the 30 patients for whom information about return to dance was available, 19 (63%; 95% CI = 43.9-79.5%) had returned to dance at an average of 8.8 months (±3.6 months) after PAO. With the numbers available we did not identify any factors associated with returning to dance in this cohort. Improvement in hip pain, sports-related activities and hip function may be expected following PAO in young female dancers. Most female dancers can expect to return to dance during the first year after surgery.

Periacetabular osteotomy for developmental hip dysplasia with labral tears: is arthrotomy or arthroscopy required?

Patients with developmental dysplasia of the hip (DDH) who undergo periacetabular osteotomy (PAO) often have labral tears. The objective of this retrospective study was to compare PAO alone with PAO combined with arthrotomy or arthroscopy in DDH patients who had a full-thickness labral tear on magnetic resonance imaging. In total, 47 hips in the PAO group (PAO) were compared with 60 hips in the PAO with concomitant arthrotomy or arthroscopy (PAO-A) with respect to Hip Disability and Osteoarthritis Outcome Score (HOOS), modified Harris Hip Score (mHHS), Visual Analog Scale (VAS), clinical and radiographic outcomes at a median of 29 months. Reoperation rate and complications were compared between two groups of treatment. The PAO group was younger than the PAO-A group (25.2 ± 9.7 versus 31.3 ± 8.3). The PAO group was more likely to have worse dysplasia: lateral center edge angle (7.6°±9.63° versus 10.8°±6.85°) and anterior center edge angle (4°±12.92° versus 10.8°±9.92°). The PAO group had a higher preoperative mHHS (65.2 ± 15.3 versus 57.8 ± 14.8) and HOOS (66.3 ± 17.5 versus 55.8 ± 20.1). There were no significant differences in final functional outcome scores across treatment groups: mHHS (PAO; 86.8 ± 12.4 versus PAO-A, 83.3 ± 17.2), HOOS (86.5 ± 13.3 versus 82.5 ± 16.8) and VAS (2.5 ± 2.8 versus 2.5 ± 3.1). There was no difference in reoperation rate between two groups (6.4% versus 11.6%, P = 0.51). The overall complication rate was lower in the PAO group (26% versus 68%), but major complications were comparable. On the basis of our data, we were not able to conclusively demonstrate a clear benefit for the routine treatment of all labral tears; however, arthrotomy or arthroscopy may play a role in some conditions.

Imaging of Proximal Tibiofibular Joint Instability: A 10 year retrospective case series.

OBJECTIVE: Detail the imaging findings in patients with proximal tibiofibular instability treated with surgical stabilization. METHODS: Retrospective analysis of preoperative imaging in patients with clinically confirmed tibiofibular instability. RESULTS: Operative fixation of the 16 patients was as follows: 11 using a fiberwire suture construct and 5 using screw fixation. Proximal tibiofibular ligamentous abnormalities were present in 100% of acute (< 6 months) and 85.7% of chronic (>6 months) instability cases who underwent MRI. CONCLUSION: MRI is sensitive in the evaluation of tibiofibular ligamentous integrity in proximal tibiofibular instability. Chronic instability should be considered in younger adults with isolated tibiofibular osteoarthritis.

The alpha angle as a predictor of contralateral slipped capital femoral epiphysis.

PURPOSE: Contralateral hip involvement in slipped capital femoral epiphysis (SCFE) is common. Femoral head-neck asphericity, as measured by an elevated alpha angle, has not previously been assessed with respect to SCFE risk. Our aim was to assess the utility of the alpha angle in predicting contralateral SCFE. METHODS: We retrospectively reviewed 168 patients (94 males) managed surgically for unilateral SCFE between 2001 and 2013 who had a minimum of 18 months follow-up. The alpha angle, the posterior sloping angle (PSA), and the modified Oxford score were recorded for every patient at the time of initial SCFE presentation. Follow-up clinical records and radiographs were assessed to determine the presence of absence of contralateral SCFE. RESULTS: Forty-five patients (27 %) developed a contralateral SCFE. Patients who developed a contralateral SCFE had a significantly higher alpha angle (51° vs 45°, p < 0.001) than patients who did not develop a contralateral SCFE. There was no significant difference in PSA or modified Oxford score (both p > 0.10) between patients who developed a contralateral SCFE and those who did not. Using a proposed alpha angle of 50.5° as a threshold for prophylactic fixation, 26 (58 %) of the 45 cases of contralateral SCFE in our study would have been prevented and 18 (15 %) of 123 patients would have undergone fixation unnecessarily. CONCLUSIONS: We found the alpha angle to positively correlate with contralateral SCFE risk. Patients with significantly elevated alpha angles may be at greater risk of contralateral SCFE and benefit from further investigation or prophylactic hip fixation.