Journal of Children's Orthopaedics

Femoral osteochondritis dissecans (OCD) is a disorder of unknown aetiology and variable prognosis that causes knee pain. In this paper, the authors study the impact of lower limb malalignment on the development and prognosis of OCD.

After anteroposterior (AP) and lateral radiograph and MRI of the knee, 53 cases of OCD were diagnosed. All patients were studied by standing full-length AP radiograph of the lower extremities in order to analyse the relationship between the femorotibial and mechanical axis and the location and stability of the osteochondritis.

The OCD lesion was located in the medial condyle (zone 2) in 75.5% of cases (40 cases). The lateral condyle was affected in 24.5% of cases (zone 4 in nine cases and zone 5 in four cases). The femorotibial angle (anatomical axis) was normally aligned in 68% of cases. A valgus deformity was observed in 9.5% of cases and a varus deformity in 22.5%. The mechanical axis of the limb appeared normal in only 32% of cases, with medial deviation in 53%, and lateral deviation in 15% of cases. When the OCD lesion was located in the medial condyle (40 cases), the mechanical axis also crossed the knee through the medial zone in 28 cases. When the OCD lesion was located in the lateral condyle (13 cases), the mechanical axis crossed the knee through zones 1 or 2 in four cases. In stable OCD, the mechanical axis and location of the lesion coincided in 19 of 36 cases (52%), compared with 16 of 17 cases (94%) in unstable OCD.

There is a high correlation between OCD location and lower limb mechanical axis deviation. The convergence of the mechanical axis with the location of the OCD lesion may be considered an associated factor in fragment instability. This convergence is more common in unstable OCD.

There are a range of implants for fixation of proximal femoral osteotomies (PFOs) in children. We investigated the training experiences and preferences of orthopaedic residents and fellows who were learning PFO, using a fixed angled blade plate (ABP) or a locking, cannulated blade plate (LCBP). We also studied short-term technical and radiographic outcomes.

This was a prospective, parallel-group, cohort study of 90 consecutive children and adolescents with cerebral palsy who underwent bilateral PFOs with ABP or LCBP. Surgical trainees completed a questionnaire to document the ease or difficulty of each operative step.

There were 48 boys and 42 girls, with a mean age of eight years and a mean follow-up of 25 months. Trainees preferred the LCBP system for: insertion of the guidewire, the seating chisel and the blade plate, as well as overall technical ease of use (p < 0.001). Radiographic outcomes were similar with no between-group differences for migration percentage (p = 0.996) or neck shaft angle (p = 0.849), but there was a higher prevalence of technical errors in the ABP group.

Trainee surgeons expressed a preference for LCBPs when learning PFO in children with cerebral palsy. Radiographic outcomes were similar in both groups, with close attending surgeon supervision.

Medial hamstring fractional lengthening is commonly performed in children with cerebral palsy (CP) to decrease contracture and/or to improve gait. Percutaneous procedures are gaining more and more popularity, even in the paediatric population, with equivocal results. The purpose of this paper was to determine the efficacy and safety of percutaneous medial hamstring myofascial lengthening (PHL).

This is a prospective randomised controlled trial including 31 knees from 18 consecutive patients with CP scheduled for medial hamstring lengthening in the setting of multilevel tendon lengthening procedures in a university hospital. Other concomitant lower extremity surgeries were not exclusionary. A first paediatric orthopaedic surgeon executes the PHL at one level, as recently described in the literature. Another surgeon opens and extends the wound to explore what had been cut during the PHL and completes fractional lengthening (OHL) of both the semimembranosus (SM) and semitendinosus (ST) when possible. Popliteal angle (PA) was assessed by a third surgeon immediately before PHL, after PHL and then after OHL, using a goniometer in a standardised reproducible manner. All three surgeons were blinded to the others’ findings. Primary endpoints included ease of performing PHL, the percentage of tendon-fascia/ muscle portion sectioned percutaneously and improvement of PA. Comparison between improvement of PA after PHL and OHL was done using a paired t-test with a 95% confidence interval.

The first surgeon was at ease in palpating and identifying the semimembranosus tendon before PHL in ten knees only. PHL led to an undesirable cut of the semimembranosus muscle fibres to more than 50% of the muscle section area in eight cases (<50% in 23 cases, between 50% and 75% in eight cases), and of the semitendinosus muscle fibres to more than 50% in all cases (complete rupture in six cases, more than 75% in eight cases and approximately 50% in 17 cases). Mean PA measured 52° pre-operatively and decreased to 40° after PHL. After OHL, the PA averaged 22°. There was a significant difference between the PA value after PHL (M = 40, SD = 11.8) and the PA value after OHL (M = 22, SD = 8.7), p < 0.0001. The gain in PA did not correlate with the extent of semimembranosus muscle divided (p = 0.38) nor with the extent of semitendinosus muscle divided (p = 0.35). No major iatrogenic neurovascular injury was observed.

To the authors’ knowledge, this is the first prospective study concerning the anatomic effects of PHL. Although it is a quick procedure, it is often associated with difficulty by the operating surgeon to identify and evaluate what should be cut percutaneously, leading to abusive injury of the muscle itself rather than the fascia alone. In addition, the gain in PA is statistically less following PHL than following OHL despite undesirable extensive muscle injury following PHL. This may be due to the multiple fascial cuts (fractional lengthening) usually performed in OHL.

The purpose of this study is to evaluate the effects of allogenic costal cartilage transplantation on preventing bony bridge formation and angular deformities for the treatment of partial growth plate injury using a rabbit model.

An experimental model of partial growth injury was created by resecting the medial part of the proximal tibial growth plate in male six-week-old New Zealand White rabbits. The rabbits were divided into four groups: no surgery; no transplantation; bone wax transplantation; and allogenic costal cartilage transplantation. The angular deformities of the tibia and bony bridge were analysed using radiographs and microcomputed tomography, and the repair of the injured growth plate cartilage and bony bridge formation rate were histologically evaluated.

On radiographic evaluation, the varus deformities in the costal cartilage group were significantly improved compared with the no transplantation group at four and eight weeks after operation and with the bone wax group at eight weeks after operation. Micro-computed tomography showed that the bony bridge formation was prevented in the bone wax and costal cartilage groups. Histological findings showed that the bony bridge formation in the bone wax and costal cartilage group was decreased. In addition, the growth plate was continuous and stained with safranin O and immunohistochemically stained for type II collagen.

Transplantation of costal cartilage improved angular deformities and decreased bony bridge formation in the partial growth plate injury. Costal cartilage might be a suitable graft for the treatment of growth plate injury.

To evaluate the clinical and radiological outcomes of using fibular strut grafts as a fixation device for non-united femoral neck fractures in children with or without subtrochanteric valgus osteotomy.

A total of 12 children with non-united femoral neck fractures (nine males and three females) with an average age of 8.2 years (5 to 12) were managed, and functional results evaluated, between July 2013 and July 2015. The mechanisms of injury were fall from a height in ten patients and road traffic accident in two cases. Nine cases of femoral neck nonunion followed failed internal fixation and three cases were neglected fractures. Six cases were treated by fibular strut graft and subtrochanteric valgus osteotomy with contoured plate and six cases were treated by fibular strut graft and hip spica.

The mean follow-up period was 20.4 months (12 to 36). Union was achieved in all 12 cases by a mean of 3.5 months (2.5 to 6). All patients were satisfied at five months. For final analysis of clinical and radiographic results, the Ratliff's classification was used. We classed 11 cases as good results and one case as fair.

Fibular strut grafts are a reliable option for treatment of pseudo-arthrosis in femoral neck fracture nonunion in children. It is successful in restoration of femoral neck length in children with non-united femoral neck fractures.

Intra-operative imaging plays a key role in screw placement for slipped capital femoral epiphysis (SCFE). Complications have been associated with inadequate screw position. The purpose of this study was to evaluate computed tomography (CT) (3D fluoroscopy) and standard fluoroscopy (C-arm) images as compared with direct anatomic measurement to determine final screw position in a cadaveric SCFE model.

Osteotomy with pinning was performed at the physeal scar in ten cadaveric hips. A standardised approach-withdrawal technique was performed with C-arm images taken at 15° increments. We also obtained a CT (3D fluoroscopy) scan of each hip. The screw tip-subchondral bone (STSB) distance was measured on digital imaging software and also with a digital calliper directly when the femoral head was cut in plane to expose the STSB distance anatomically. Statistical analysis included t-tests and Fisher's exact test.

Moderate SCFE osteotomies were achieved with a mean Southwick angle (39.5° ± 7°). The 60° fluoroscopic image was found to be the most representative image (41% of the time) compared with both anteroposterior (AP) and lateral images (8% and 21%). Both fluoroscopy (2.7 ± 0.8 mm, p < 0.001) and CT (1.6 ± 0.7 mm, p = 0.03) overestimated the STSB distance compared with direct measurement (0.94 ±  0.51 mm). Two-thirds (67%) of CT measurements were within 1 mm of the cadaveric measurement, while only 20% of C-arm measurements fulfilled this criterion (p = 0.04).

Both standard fluoroscopy and CT overestimated the STSB distance when compared with direct measurement in a cadaveric model of SCFE. Surgeons should be aware of the limitations of intra-operative imaging to determine the STSB distance. We suggest that using the known pitch of a screw (2.9 mm in a 7.3-mm cannulated screw) as an intra-operative tool to help guide screw placement.

Theoretically, dynamic thoracic compliance (DTC) should be reduced by vertical expandable prosthetic titanium ribs (VEPTR) since titanium rods, scar tissue and ossifications increase stiffness of the rib cage. The effect of VEPTR on thoracic compliance has not yet been elucidated. The impact of VEPTR on the development of sagittal balance has not been fully investigated.

In a retrospective study, we investigated 21 consecutive children who were treated by VEPTR from 2004 to 2011 and three control groups. We compared the development of thoracic compliance during growth to Nr1. Development of sagittal balance during growth was compared to Nr2 and to Nr3 (which has been instrumented from ileum to rib). Mean follow-up was 60.67 months (standard error of the mean (SE 4.77).

The difference of change of DTC during growth of VEPTR group versus a control group was not significant (p < 0.05). However, initial DTC and DTC at last follow-up of VEPTR group were lower than DTC of the control group. The difference was significant (p < 0.05). Mean correction of Cobb angle after the first operation was 16.41° (SE 3.01). Until last follow-up, we saw a loss of correction of 8.23° (SE 3.22). The differences between the development of parameters of sagittal balance during growth between the VEPTR group, control group 2 and control group 3 were not significant (p > 0.05).

VEPTR treatment should start as early as possible since VEPTR seems to lead to an increased rate of DTC that is similar to healthy controls. Sagittal balance showed a similar development as in healthy children.

The aim of this article was to review the incidence, presentation, treatment and complications of paediatric pelvic fractures of children who were admitted to our level 1 trauma centre and to compare them with our data from adult pelvic fracture patients.

We conducted a retrospective chart review of all children with pelvic fractures who were managed at our institution between January 1993 and December 2013 and compared the data with our database on pelvic fractures in adults during the period 2007 to 2012.

We identified 51 children and 268 adults with pelvic fractures. The median age of the paediatric patients was 11 years. Children were significantly more involved in traffic accidents than adults (p < 0.001). Adults had a significantly higher Injury Severity Score (ISS) (31 vs 24.5; p < 0.03) and were significantly more often haemodynamically unstable (p < 0.01). Adults had a type C fracture more often, while children had a type B fracture (p < 0.001). Associated injuries were seen in both groups; however, thoracic injuries were significantly higher in adults (p < 0.01) and injuries to the extremities were higher in children (p < 0.01). Adults were significantly more often treated with open reduction and internal fixation (p < 0.001). Mortality in both groups, however, did not differ (6% vs 8%).

Paediatric pelvic fractures are rare. They differ from adult pelvic fractures in presentation, associated injuries and management. Mortality, however, is substantial and does not differ from the adult population. Mortality is often due to concomitant injuries and not to exsanguination from the pelvic fracture.

To review all paediatric ankle syndesmotic injuries occurring at our institution and identify risk factors associated with operative intervention.

Among 22 873 evaluations for ankle trauma, we found 220 children suffering from syndesmotic injuries (incidence: 0.96%). We recorded demographic data, details of the injury, features on examination and treatment variables. Univariable and multivariable logistic regression modelling was performed to identify risk factors associated with operative intervention.

The mean age at injury was 15.8 years (8.9 to 19.0) with a median follow-up of 13 weeks (IQR 5 to 30 weeks). A sports-related injury was most common (168/220, 76%). A total of 82 of 220 (37%) patients underwent operative fixation, of which 76 (93%) had an associated fibular fracture. Patients undergoing surgery had a higher incidence of swelling and inability to weight bear (p < 0.001). Statistically significant differences were recorded in tibiofibular (TF) clear space, TF overlap and medial clear space (MCS) between the operative and non-operative cohorts (6.0 vs 4.6 mm (p = 0.002), 5.4 vs 6.9 mm (p = 0.004) and 6.4 vs 3.5 mm (p < 0.001)). Multivariable analysis revealed patients with a fracture of the ankle had 44 times the odds of surgical intervention, patients with a closed physis had over five times the odds of surgical intervention and patients with a medial clear space greater than 5 mm had nearly eight times the odds of requiring surgical intervention.

Operative ankle syndesmotic injuries in the paediatric population are often associated with a closed distal tibial physis and concomitant fibular fracture.

The severe form of coxa vara, the ‘shepherd's crook deformity’, is always a consequence of a locally extensive form of polyostotic fibrous dysplasia (or McCune-Albright syndrome). Treatment of this deformity is a challenge. The soft bone does not tolerate any implant that depends on the stability of the cortical bone (like plates or external fixators). Intramedullary nails are the most appropriate implants for stabilisation, but if they are inserted from the greater trochanter, they cannot correct the varus deformity enough.

We have developed a special intramedullary nail that can be inserted from the osteotomy site and can be driven retrograde into the femoral neck in an appropriate valgus position. We have operated 15 legs in 13 patients. The average age at surgery was 14 years and 5 months (6 to 28.9). In all, 11 femora had been operated before (unsuccessfully) with various implants.

The average follow-up was 54.2 months (7 to 132). The average correction of the neck/(distal) shaft angle was 57.5° (10° to 80°) (= 72.8%). While pre-operatively none of the patients was able to walk without aid, at follow-up only one patient was unable to walk, three used the aid of crutches because of tibial lesions and one patient had an increased external rotation of the leg. At follow-up, most patients were free of pain. One implant broke and had to be replaced.

This new operative method offers the possibility of efficient correction and stabilisation of this severe and difficult deformation.

The Avon Longitudinal Study of Parents and Children (ALSPAC) prospective cohort was used to determine the accuracy of the Paley multiplier method for predicting leg length. Using menarche as a proxy, physiological age was then used to increase the accuracy of the multiplier.

Chronological age was corrected in female patients over the age of eight years with documented date of first menses. Final sub-ischial leg length and predicted final leg length were predicted for all data points.

Good correlation was demonstrated between the Paley and ALSPAC data. The average error in prediction depended on the time of assessment, tending to improve as the child got older. It varied from 2.2 cm at the age of seven years to 1.8 cm at the age of 14 years. When chronological age was corrected, the accuracy of multiplier increased. Age correction of 50% improved multiplier predictions by up to 28%.

There appears to have been no significant change in growth trajectories of the two populations who were chronologically separated by 40 years. While the Paley data were based on extracting trends from averaged data, the ALSPAC dataset provides descriptive statistics from which it is possible to compare populations and assess the accuracy of the multiplier method. The data suggest that the accuracy improves as the patient gets close to the average skeletal maturity but that results need to be interpreted in conjunction with a radiological assessment of the growth plates. The magnitude of the errors in prediction suggest that when using the multiplier, the clinician must remain vigilant and prepared to perform a contralateral epiphyseodisis if the prediction proves to be wrong. The data suggest a relationship between the multiplier and menarche. There appears to be a factorisation and when accounting for physiological age, one needs to correct by 50% of the difference between chronological and physiological age.

Renal osteodystrophy (ROD) may cause severe lower limb deformities in children. The purpose of this study is to evaluate the efficacy of the temporary hemiepiphysiodesis for the correction of lower limb deformities in children with ROD.

Guided growth correction by hemiepiphysiodesis has been performed in skeletally immature patients with deformities of the lower limbs caused by ROD. The correction of the mechanical axes of the lower limbs and its correction speed have been evaluated.

A total of seven patients with ROD, five males and two females, were treated with the above technique. The average age of the patients at their first surgery was 7.8 years (2.9 to 13.6). The average follow-up time 5.2 years (2.3 to 8). There were 13 valgus deformities and one varus deformity of the knee. The measure of the lower limb angular deformity was in the range of 10° to 47°. Restoration of normal mechanical axis was achieved in all patients at the final follow-up. Three patients relapsed and required further hemiepiphysiodesis. The average time for correction was 20 months (7 to 30). The average speed of correction was 0.49° per month for a tibia and 1.73° per month for a femur. There were two minor complications: a screw mobilisation and a screw breakage occurred during removal.

Guided growth technique by hemiepiphysiodesis is a mini-invasive surgical procedure that has been found to be effective for the correction of misalignment due to ROD in skeletally immature patients. The method has allowed progressive correction of the deformities at any age in childhood. These patients are predisposed to relapse to their deformities, thus a strict follow-up is required.