The Long-Term Outcome After Varus Derotational Osteotomy for Legg-Calvé-Perthes Disease: A Mean Follow-up of 42 Years

Proximal femoral varus osteotomy for Legg-Calvé-Perthes disease: Do age and lateral pillar classifications influence short-to-mid-term clinical and radiological outcomes?

INTRODUCTION

Proximal femoral varus osteotomy (FVO) is one of the most used treatment methods with acceptable outcomes for Legg-Calvé-Perthes disease (LCPD). We aimed to investigate the influence of age at disease onset and the Lateral Pillar classification on clinical and radiological outcomes of FVO surgery LCPD patients between 6-12years of age.

HYPOTHESIS

Proximal FVO surgery in the early fragmentation phase of LCPD patients led to acceptable clinical and radiographic outcomes in a 3-year follow-up, regardless of preoperative age and Herring type.

MATERIAL AND METHODS

Fifty patients with LCPD (Herring groups B, B/C, and C) who underwent FVO were retrospectively reviewed. We evaluated radiological [center-edge angle, extrusion index, epiphyseal index, acetabular index, articulo-trochanteric distance (ATD)] and clinical [hip abduction range of motion (ROM), Trendelenburg sign, pain, and Harris hip score (HHS)] outcomes with a follow-up of 37.3±10.5months (range: 24-180months). Finally, the overall treatment outcome was assessed using the Stulberg classification.

RESULTS

The ROC curve analysis did not reveal any significant relationship between age and clinical or radiological outcomes, and there was no predictable age cut-off for surgical outcomes (p=0.13). No significant difference was found in Stulberg classification at the follow-up between patients with type B, B/C, and C of the lateral pillar (p>0.05).

DISCUSSION

Our results demonstrated that open-wedge proximal FVO surgery in the early fragmentation phase of LCPD patients led to acceptable clinical and radiographic outcomes in a 3-year follow-up. Each sample of our study was very small and a lot of variables were measured, making this result not adequately strong enough to draw a robust conclusion. However, FVO surgery remains a possible suggestion for patients in the early fragmentation phase, and age and lateral pillar type may not be limiting factors.

LEVEL OF EVIDENCE

IV; therapeutic retrospective cohort.

Perthes disease: comparison of two surgical options

Varus intertrochanteric osteotomy (ITO) remains the most popular method to contain the fragmenting femoral head in Perthes disease. However, resultant compromise of hip abductors may result in coxa brevis and acetabular dysplasia, increasing the risk of requiring future surgery. A minimally invasive strategy of tension plating the greater trochanter was developed in effort to avoid these consequences. The objective is to compare greater trochanter-guided growth to ITO for treatment of Perthes disease. This IRB approved, retrospective review compares two series of children with Perthes, one treated with ITO and one with greater trochanter-guided growth (GG). Clinical examination findings and clinical course were recorded via chart review. Weight-bearing pelvic X-rays were analyzed preoperatively and at the last known follow-up prior to other procedures. There were 58 patients: 18 underwent ITO versus 40 GG. The groups matched in age, sex, examination, and radiographic parameters. Average follow-up was 5 years. The change in the center head-trochanteric distance (CTD) was statistically significant ( P < 0.05), -0.3 cm in GG versus -1.09 cm in ITO patients. At final follow-up, the ITO group was more likely to have LLD ≥ 2 cm (16.67% vs. 0%; P = 0.03) and 52.5% of GG patients were classified as Stulberg III or greater, versus 72.2% of the ITO group ( P < 0.001). Ninety-four percent of ITO patients versus 40% of GG required additional surgery. Containment by ITO reflects exclusive focus upon the femoral head, without considering long-term sequelae. GG addresses the femoral neck issues potentially providing better outcomes. Level of Evidence. This is a level III study providing further understanding of the properties of the proximal femoral physes and an alternative for surgical management of perthes disease.

Rate of Total Hip Replacement after Legg Calve Perthes Disease in a Canadian Province

Legg Calve Perthes disease is a pediatric hip condition that leads to early hip degeneration. The efficacy of operative and nonoperative treatment is not well defined in the literature. Using the rate of total hip arthroplasty as a surrogate measure for symptomatic hip degeneration, the rate of total hip arthroplasty was compared in Legg Calve Perthes disease patients with and without previous surgical intervention in the province of Manitoba, Canada. A retrospective review was conducted using de-identified, individual-level administrative records of health services for the entire population of Manitoba. Codes for Legg Calve Perthes disease, femoral osteotomies, pelvic osteotomies, adductor tenotomies, and total hip arthroplasty were searched from 1984 to 2018. The rate of total hip arthroplasty in patients with Legg Calve Perthes disease was determined for two groups: (1) patients with earlier surgical intervention and (2) patients with no previous surgical intervention. Of the 202 patients included in the study, 180 had no prior surgery and 22 had prior surgery. The rate of total hip arthroplasty between the previous operative and nonoperative groups was found to be 32% and 40%, respectively (p = 0.458). There was no significant difference in rates of total hip arthroplasty in the operative and nonoperative groups. Further prospective studies are required to elucidate the differences in outcomes between operative and nonoperative treatment groups in patients with Legg Calve Perthes disease.

Long-Term Outcomes at Skeletal Maturity of Combined Pelvic and Femoral Osteotomy for the Treatment of Legg-Calve-Perthes Disease

Surgical treatment for Legg-Calve-Perthes disease (LCPD) is recommended for older children with moderate to severe disease. We sought to determine whether double osteotomies lead to improved radiologic outcomes compared to reported non-operative outcomes. Patients older than 6 years of age diagnosed with LCPD lateral pillar B or C who were treated with pelvic and femoral osteotomies were included. Radiologic outcomes and leg-length discrepancies were assessed using the Stulberg classification and were compared with the current literature. Fifteen hips in fourteen patients were treated with double osteotomy for LCPD, and seven had lateral pillar C disease (47%). The mean age at surgery was 8.6 years (range, 7.2-10.4) and the mean age at follow-up was 20.2 years (range, 14.2-35.6). At a mean 11.6-year follow-up (range: 6.3-25.2), double osteotomy resulted in 40% of patients having Stulberg I/II scores, 27% having Stulberg III scores, and 33% having Stulberg IV/V scores. The mean leg-length discrepancy was 1.4 cm in lateral pillar C patients compared to 0.8 cm in lateral pillar B patients. Four patients underwent additional surgeries, including two who required total hip arthroplasty. Double osteotomy as an alternative surgical procedure for the treatment of LCPD did not show improved outcomes when compared to historic non-operative cohorts.

Does Acetabulum Remodel Following Varus Derotation Osteotomy for Perthes' Disease?

Objective  We investigated the effect of disease stage, patient's age and final contour of femoral head on acetabulum contour following varus derotation osteotomy of proximal femur (VDRO) in unilateral Perthes's disease. Methods  The study is a retrospective analysis of case records of 23 children aged ≥6 years with unilateral Perthes' disease who underwent primary VDRO procedure for containment. Acetabular index (AI) and center edge angle (CEA) were calculated bilaterally in preoperative and follow-up radiographs and compared statistically. Results  There were 15 boys and 8 girls. Six hips were in Ib, 8 in IIa and 9 in IIb modified Waldenström stage while undergoing VDRO. The mean age at surgical intervention was 8.7 years. The mean follow-up duration was 3.5 years. All femoral heads were healed at final follow-up and the final Stulberg grades were I = 3, II = 8, III = 7, IV = 5. A significant acetabular dysplasia on the affected side was present preoperatively. At follow-up, the patients operated had significantly raised AI and reduced CEA. There was no significant acetabular remodeling of the affected hips at follow-up even in children operated at younger age (< 8 years) or early stages (stage Ib or IIa). The acetabulum remodeling did not correspond to the final Stulberg grade as well. Conclusion  Acetabulum was found involved in early stages of Perthes' disease. Varus derotation femoral osteotomy for the diseased hip showed no significant improvement in acetabular dysplasia even when operated in early disease stages or younger age group. Residual acetabular changes were also noted even with favorable Stulberg grades.

Does Flexion Varus Osteotomy Improve Radiographic Findings Compared With Patients Treated in a Brace for Late-onset Legg-Calvé-Perthes Disease?

BACKGROUND

Legg-Calvé-Perthes disease (LCPD) is a childhood hip disease characterized by osteonecrosis of the femoral head. Because severe deformity of the femoral head can cause secondary osteoarthritis in adulthood, progressive collapse should be prevented in children with a necrotic epiphysis. The prognosis of patients with LCPD generally worsens as the age at disease onset increases, and the appropriate treatment for late-onset LCPD remains unclear. Based on the limited effect of nonoperative treatment using a nonweightbearing brace, flexion varus osteotomy (FVO) was introduced in 2010 as an initial treatment for late-onset LCPD in place of brace treatment, which we used in our institution before that time.

QUESTIONS/PURPOSES

We asked, (1) Which treatment, FVO or a nonweightbearing brace, is associated with a lower likelihood of progressive femoral head collapse in children whose diagnosis of LCPD was made at the age of ≥ 8 years and who were followed for a minimum of 3 years after their intervention? (2) What proportion of patients in the brace group had surgery despite the treatment, and what percentage of children in the FVO group had a second operation to remove hardware and/or additional operations?

METHODS

The initial treatment was applied in 181 patients with LCPD between 1995 and 2018 in our institution. Patients whose disease onset was at ≥ 8 years old (late-onset LCPD) with complete clinical and radiologic data were considered potentially eligible. In 2010, treatment for these patients changed from brace treatment to FVO for all patients. A total of 35% (42 of 121) of patients who were treated with a nonweightbearing brace between 1995 and 2009 and 40% (24 of 60) of patients who were treated with FVO between 2010 and 2018 were eligible. Among patients treated with a brace, 21% (nine of 42 patients) were excluded because of hospital transfer (three patients), short-term follow-up (three), the period from onset to the first visit was ≥ 7 months (two), and inability to use the brace because of mental incapacity (one patient). In patients treated with FVO, 12% (three of 24 patients) were excluded (two patients with a period from onset to the first visit ≥ 7 months and one with a comorbidity and multiple-epiphyseal dysplasia). Among the remaining patients, 79% (33 of 42 patients) were classified into the brace group and 88% (21 of 24 patients) were classified into the FVO group for analyses. There were no overlapping patients at the timepoint when the treatment strategy for late-onset LCPD changed. In the FVO group, subtrochanteric osteotomy with 35° to 40° of flexion and 15° to 20° of varus was performed using a locking compression plate for pediatric use. Patient demographics, radiographic parameters, and the assessment of femoral head deformity using the Stulberg classification were compared between the two groups. There was a greater proportion of boys than girls in both groups (brace: 88% and FVO: 86%), and there were no differences in the distribution of genders between the groups (p = 0.82). The right side was more frequently treated in the brace group, but there was no difference in laterality between the groups (brace: 58% right and FVO: 62% left; p = 0.16). There was no difference between groups in the median age at disease onset (9.0 years [range 8.0 to 12.5 years] in the brace group and 9.6 years [range 8.0 to 12.4 years] in the FVO group; p = 0.26). There was no difference between the groups in the period of treatment from onset (1.7 ± 1.9 months in the brace group and 1.5 ± 1.5 months in the FVO group; p = 0.73) or the follow-up period (6.7 ± 2.1 years in the brace group and 6.2 ± 2.1 years in the FVO group; p = 0.41). The LCPD stage at the first visit was assessed using the modified Waldenström classification. The intraobserver and interobserver values of the modified Waldenström classification, evaluated using kappa statistics, were excellent (kappa value 0.89 [95% CI 0.75 to 0.97]; p < 0.01) and good (kappa value 0.65 [95% CI 0.43 to 0.87]; p < 0.01). The radiographic degree of collapse at the maximum fragmentation stage was assessed using the lateral pillar classification. The intraobserver and interobserver reliabilities of the lateral pillar classification were excellent (kappa value 0.84 [95% CI 0.73 to 0.94]; p < 0.01) and excellent (kappa value 0.83 [95% CI 0.71 to 0.94]; p < 0.01). The degree of femoral head deformity at the most recent follow-up examination was compared between the groups in terms of the Stulberg classification, in which Classes I and II were classified as good and Classes III through V were classified as poor. The intraobserver and interobserver reliabilities of the Stulberg classification were good (kappa value 0.74 [95% CI 0.55 to 0.92]; p < 0.01) and good (kappa value 0.69 [95% CI 0.50 to 0.89]; p < 0.01). The evaluators were involved in the patients' clinical care as part of the treating team.

RESULTS

Good radiographic results (Stulberg Class I or II) were obtained more frequently in the FVO group (76% [16 of 21 patients]) than in the brace group (36% [12 of 33 patients]), with an odds ratio of 5.6 (95% CI 1.7 to 18.5; p < 0.01). In the brace group, a subsequent femoral varus osteotomy was performed in 18% (six of 33) of patients with progressive collapse and hinge abduction, and implant removal surgery was performed approximately 1 year after the first procedure. This traditional varus osteotomy was occasionally performed in patients who were considered for conversion from nonoperative treatment before 2009 because FVO had not yet been introduced. In the FVO group, all patients (n = 21) had a second procedure to remove the implant at a mean of 10.5 ± 1.2 months postoperatively. Additional procedures were performed in 24% (five of 21) of patients, including a second FVO for progressive collapse (one patient), guided growth for a limb length discrepancy (one patient), and flexion valgus osteotomy for coxa vara in patients with a limb length discrepancy (three patients).

CONCLUSION

Our historical control study found that FVO may increase the possibility of obtaining good radiographic results (Stulberg Class I or II) compared with brace treatment for patients with late-onset LCPD, although surgical interventions after the first and second implant removal procedures may be indicated. Surgeons can consider FVO if they encounter patients with late-onset LCPD, which is a challenging condition. A larger study with long-term follow-up is needed to confirm the efficacy of FVO.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Incidence of total hip arthroplasty in patients with Legg-Calve-Perthes disease after conservative or surgical treatment: a meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to determine the incidence of total hip arthroplasty (THA) in patients with Legg-Calve-Perthes disease (LCPD) treated conservatively or surgically and factors influencing the incidence of THA.

METHODS

Long-term follow-up studies on the conservative or surgical treatments of LCPD from 1950 to 2021 were conducted using six public databases. Articles were screened by two investigators (PRISMA guidelines), and the quality of the included publications (n = 27) was assessed (MINORS criteria). R version 4.2.1 was used for statistical analysis.

RESULTS

The overall incidences of THA were 6.8% and 5.14% in patients who were treated conservatively and surgically, respectively. At disease onset, the incidences of THA were 6.79% and 6.17% after conservative treatment and surgery in patients aged < seven years, respectively, and 16.97% and 3.61% in patients aged > seven years, respectively. The incidences of THA were 4.91%, 5.19%, and 23.18% in patients who were treated conservatively with ≤ 30, 30-40, and > 40 years of follow-up, respectively, and 3.68%, 3.11%, 9.66%, and 17.92% in patients who were treated surgically with ≤ ten, ten to 20, 20-40, and > 40 years of follow-up, respectively. In patients who received conservative treatment, the incidences of THA were 5.79% and 5.29% in patients with Stulberg I-II and III-V, respectively. In surgically treated patients, the incidence of THA was 0% in Stulberg I-II and 8% in Stulberg III-V.

CONCLUSION

Patients with LCPD had relatively low incidences of THA. The greater the age at disease onset and longer the follow-up, the higher the incidence of THA; however, the Stulberg classification was not directly associated with the incidence of THA.

Does Prolonged Weight Relief Increase the Chances of a Favourable Outcome After Containment for Perthes Disease?

We have been treating children with Legg-Calvé-Perthes disease (LCPD) with a femoral varus osteotomy (PFVO) and weight relief till the disease evolves to the latter part of the stage of reconstitution (Stage IIIb). This entails weight relief for 18 to 24 months. We undertook this case-control study to test if a shorter period of weight relief would compromise the chance of retaining the spherical shape of the femoral head when the disease healed. Forty-one children diagnosed in the early stages of LCPD (Stages Ia, Ib, and IIa), were treated by PFVO and non-weight-bearing for a period of 6 months following surgery (6m group). Eighty-two children with LCPD matched for age, sex, and stage at surgery, who resumed weight-bearing only once they reached Stage IIIb, served as the control group (3b group). Both groups were followed up till the disease healed. The sphericity deviation score was calculated, and the height and width of the epiphysis were measured on the first radiograph designated as Stage IV. The median sphericity deviation score value at healing was 3 in the 3b group and 11 in the 6m group (P<0.001). The frequency of spherical heads was 76% in the 3b group and 49% in the 6m group (P<0.003). The Odds Ratio of the disease healing with an aspherical head in 6-month group was 3.05 (CI: 1.28 to 7.22) compared with the 3b group. The percentage increase in width of the femoral epiphysis at healing was greater in the 6 group (111.5±8.5% vs. 106.5±7.2%; P<0.001). The study confirms that containment by PFVO performed early in the course of LCPD combined with weight relief till the disease has evolved to Stage IIIb is likely to result in spherical hips in 75% of children. Reducing the period of weight relief to 6 months may yield significantly poorer results with only 49% spherical femoral heads.

RADIOGRAPHIC STUDY OF THE MEDIAL JOINT SPACE OF THE HIP IN LEGG-CALVÉ-PERTHES DISEASE

Objective

To evaluate medial joint space in affected and normal contralateral hips in patients with Legg-Calvé-Perthes disease (LCPD).

Methods

To compare joint space, femoral head extrusion (FHE), medial space coefficient (MSC) of the hip, and femoral head width (FHW) in affected and normal hips, using 127 radiographs of patients with unilateral LCPD and considering age groups under and over six years old as well as their disease stage.

Results

No statistically significant differences were observed regarding MSC between normal and affected hips regardless of disease staging. However, medial joint distance was significantly greater in affected hips than in normal hips. In the necrosis and fragmentation phase, distance from medial space in affected hips was significantly greater than in contralateral normal hips. Comparing only affected hips, MSC and FHW showed statistically significant differences and the group > 6 yo presented higher values. Among normal hips, the group < 6 yo presented a statistically significant difference considering the MSC and FHW.

Conclusions

No statistically significant difference was found between the medial joint space of affected and normal hips, except for early stages of the disease (necrosis and fragmentation). The isolated use of radiographic study is insufficient in LCPD and the lack of complementation with other exams, such as magnetic resonance, can delay diagnosis of and onset of treatment for the disease. Level of Evidence III, Study of Non Consecutive Patients; without Consistently Applied Reference "Gold" Standard.

Proximale Varisationsosteotomie des Femurs beim Morbus Perthes

Operationsziel

Die proximale femorale Varisationsosteotomie (PVO) ist eine chirurgische Technik zur Rezentrierung des Hüftkopfes, sofern es bspw. im Rahmen der ablaufenden Legg-Calvé-Perthes(LCPD)-Krankheit zur Subluxation gekommen ist.

Indikationen

Bis anhin existieren keine einheitlichen Indikationskriterien für die Containment-Therapie bei LCPD-Patienten. Einzelne, für die Deformitätsentwicklung prädiktive radiologische Faktoren, Alter bei Diagnosestellung oder Symptombeginn und Klassifikationen, welche die Pathomorphologie des Femurkopfes bezogen auf die Nekrose beschreiben, können die Indikationsstellung erleichtern.

Kontraindikationen

Die absolute Kontraindikation stellt die Entwicklung eines Scharniergelenkes dar (Hinge-Abduktion). Bleibt der Femurkopf in einer Abduktionsröntgenaufnahme von 20° auch in Abwesenheit einer Hinge-Abduktion dezentriert oder besteht ein Total-Kopf-Befall, ergibt sich ebenfalls eine Kontraindikation. Relativ kontraindiziert ist die PVO bei Kindern mit Beginn der Erkrankung < 6 Jahren, in der Lateral-Pillar-Klassifikation Gruppe A soiwe bei I und II nach Catterall.

Operationstechnik

Lateraler Standardzugang zum proximalen Femur. Platzieren des Anteversions-K-Drahtes ventral des Schenkelhalses. Weitere K-Drähte werden parallel mithilfe von Positionierinstrumenten in den Schenkelhals eingebracht. Der optimale Bereich für die Osteotomie wird aufgesucht. Für die Vereinfachung der Manipulation des distalen Fragments und als Referenz für die Derotation werden am Femurschaft weitere K‑Drähte eingebracht. Nach Femurosteotomie erfolgt proximales Fixieren der Platte durch sukzessives Auswechseln der K‑Drähte gegen winkelstabile Schrauben. Die interfragmentäre Kompression erzeugt eine exzentrisch positionierte Kortikalisschraube im mittleren distalen Plattenloch. Die weitere distale Fixation der Platte erfolgt mit winkelstabilen Schrauben. Auswechseln der Kortikalisschraube gegen eine weitere winkelstabile Schraube. Alternativ zur hier beschriebenen winkelstabilen Technik wurde früher meist mittels Winkelplatte korrigiert.

Weiterbehandlung

Mobilisation unter Abrollbelastung an 2 Gehstöcken über 6 Wochen. Röntgenkontrolle und bei genügender Knochenkonsolidation Steigerung der Belastung. Implantatentfernung nach 9 bis 12 Monaten. Rückkehr zum Sport ab 3 Monaten.

Ergebnisse

Die PVO ist eine in der Behandlung von LCPD nahezu seit 60 Jahren angewendete und weltweit etablierte chirurgische Technik. Durch ein stetig wachsendes Verständnis der Grunderkrankung wird einerseits die Indikationsstellung für operative Interventionen optimiert. Andererseits tragen neue Implantate zur Verbesserung der klinisch-radiologischen Resultate und Verringerung von Komplikationen während und nach Operation bei.

[Anatomic and clinical study of virtual reality technology assisted modified transtrochanteric curved varus osteotomy for osteonecrosis of the femoral head]

OBJECTIVE

To explore the feasibility and effectiveness of the modified transtrochanteric curved varus osteotomy in the treatment of osteonecrosis of the femoral head (ONFH), clarify the key points of the operation, and then explore the effectiveness of modified transtrochanteric curved varus osteotomy in the treatment of ONFH assisted by virtual reality (VR) technology.

METHODS

A 70-year-old adult female cadaver without formaldehyde fixation was taken. It was confirmed by anatomical study and simulated operation that the modified transtrochanteric curved varus osteotomy was suitable for type C1 (patients with involvement of the lateral column of the femoral head but partial integrity) classified by the Japanese Osteonecrosis Investigation Committee (JIC). Between October 2018 and August 2020, 11 patients (17 hips) with ONFH who met the selection criteria were treated with modified transtrochanteric curved varus osteotomy. VR technology was used to simulate varus osteotomy before operation to predict the angle of valgus of lower limbs and pronation of femoral head. Osteotomy, valgus, and pronation were performed according to the results of preoperative planning. After operation, X-ray films were used to evaluate the changes of varus and neck-shaft angle after VR assisted surgery, and Harris score was used to evaluate the hip function.

RESULTS

The anteroposterior pelvic X-ray film was rechecked at 2 days after operation, of which 3 hips were consistent with the planned varus angle of VR preoperative planning, and the error value of varus angle of the remaining 14 hips was 1°-4°. The difference between VR preoperative planning and 2 days after operation was 6°-16°. All 11 patients were followed up 11-28 months, with an average of 19.2 months. All incisions healed by first intension. During the follow-up, 1 case (1 hip) developed greater trochanter fracture at 2 months after operation and was treated with open reduction and plate and screw internal fixation; 1 case (1 hip) had delayed healing at osteotomy at 4 months after operation and healed at 3 months after local injection of platelet rich plasma and oral supplementation of kidney blood-strengthening soup. At last follow-up, 17 hip osteotomies healed. The Harris score was 84.0±5.6, which was significantly higher than that before operation (57.2±5.5) ( t=-14.107, P=0.000); hip function was excellent in 2 hips, good in 13 hips, and fair in 2 hips.

CONCLUSION

The modified transtrochanteric curved varus osteotomy for the treatment of ONFH is theoretically feasible, and the short-term effectiveness of this operation combined with VR technology is satisfactory.

Surgical Treatments for Legg-Calvé-Perthes Disease: Comprehensive Review

Background

Legg-Calvé-Perthes disease (LCPD) is a common public health problem that usually occurs between the ages of 4 and 8 years, but it can occur between the ages of 2 and 15 years. This condition occurs due to the interruption of blood supply to the femoral head. Up to now, different surgical and nonsurgical treatments, including femoral varus osteotomy, innominate osteotomy, pelvic osteotomies, triple osteotomy, Chiari osteotomy, and shelf acetabuloplasty, have been suggested for noncontainable LCPD hips.

Objective

The aim of this comprehensive review was to investigate the various surgical techniques used for LCPD.

Methods

An advanced electronic search of the English-language literature was performed from October 8 to 14, 2020. The electronic databases PubMed, MEDLINE, Web of Science, Embase, Ovid, and Google scholar were searched using appropriate search terms. A manual search of references also was performed. After retrieving the studies, duplicates were removed, and the remining studies were screened based on the title, abstract, and full text. The quality of the selected articles was assessed, and the required data were extracted from eligible articles.

Results

A total of 22 studies were included in the review. Based on the results of the reviewed studies, there are three main factors that influence the treatment outcomes in patients with Perthes disease. These factors are onset age, femoral head involvement severity, and treatment method. The disease has a poor prognosis in children over 8 years old, but this group of patients can also benefit from advanced surgical methods. In patients aged less than 6 years, the disease has a generally good prognosis, but in those aged between 6 and 8 years, its prognosis is variable. Thus, the need for surgical intervention requires close observation of signs. Once any head signs are observed, dynamic arthrography is beneficial before choosing the treatment approach.

Conclusions

This review provides clinicians with a brief guideline for the treatment of patients with LCPD.

Femoral Neck Fractures in Children: Issues, Challenges, and Solutions

Femoral neck fractures in children are rare injuries resulting from high-energy trauma. Different methods of treatment, lack of standard management protocols, and the high risk of complications make this injury one of the biggest challenges that an orthopaedic surgeon can face. This review focuses on the general aspects of the pediatric femoral neck fracture management as well as its complications and possible solutions.

Agreement of radiographic measurements and patient-reported outcome in 61 patients with Legg-Calvé-Perthes disease at mean follow-up of 28 years

It is unclear how patient-reported outcome in patients with Legg-Calvé-Perthes disease (LCPD) is correlated with radiographic outcome. It was therefore the aim of our long-term follow-up to evaluate the agreement of patient-reported outcome measures (PROM) with radiographic outcome in patients with a history of unilateral LCPD and a femoral head involvement of more than 50%. We further investigated to what extent the functional outcome (range of motion and Trendelenburg sign) correlates with PROM and radiographic outcome. At a mean follow-up of 28 years (15-42), 61 patients were investigated clinically and by plain radiography to evaluate the sphericity deviation score, femoral head enlargement and femoral neck growth inhibition. The patients also completed questionnaires for generic measures of health-related quality-of-life (ED-5D, EQ-visual analogue scale), the joint-specific Harris hip score and the nonarthritic hip score questionnaire. The radiographic measures sphericity deviation score, femoral head enlargement and femoral neck growth inhibition were strongly correlated with the joint-specific PROMs (Harris hip score and nonarthritic hip score) but not with EQ-5D and EQ-visual analogue scale. Inferior range of flexion and abduction and a positive Trendelenburg sign were associated with an inferior patient-reported outcome. Our findings highlight the importance of supporting femoral head re-modelling and containment and balancing trochanteric and femoral neck growth in patients with LCPD. To capture the whole picture of the outcome after LCPD, future studies should include a combination of radiographic measurements and joint-specific and generic outcome scores. Level of Evidence: Level III.

What's New in Pediatric Hip?

BACKGROUND

Developmental dysplasia of the hip (DDH), which encompasses a wide spectrum of disease from mild dysplasia to frank dislocation, is one of the most common developmental deformities of the lower extremities and one of the leading causes of future osteoarthritis and hip arthroplasty. Legg-Calvé-Perthes disease (LCPD) results from a vascular insult to the growing femoral epiphysis, which in turn can create permanent morphologic changes to the hip joint. Slipped capital femoral epiphysis (SCFE) occurs when the proximal femoral physis fails allowing the epiphysis to displace in relation to the metaphysis. Infections about the hip also create significant morbidity in the pediatric hip.

METHODS

We searched the PubMed database for all studies related to DDH, LCPD, SCFE, and pediatric hip infections that were published between July 1, 2014 and August 31, 2017. The search was limited to English articles and yielded 839 papers. This project was initiated by the Pediatric Orthopaedic Society of North America Publications Committee and was reviewed and approved by the Pediatric Orthopaedic Society of North America Presidential Line.

RESULTS

A total of 40 papers were selected for review based upon new and significant findings. Select historical manuscripts are also included to provide sufficient background information.

CONCLUSIONS

DDH, LCPD, SCFE, and infections about the hip continue to be important topics in pediatric orthopaedics and areas of vital research. This manuscript reviews the most important recent literature on the diagnosis and treatment of these pediatric hip conditions.

LEVEL OF EVIDENCE

Level V.

Drilling Combined with Adipose-derived Stem Cells and Bone Morphogenetic Protein-2 to Treat Femoral Head Epiphyseal Necrosis in Juvenile Rabbits

This study was designed to evaluate the effects of drilling through the growth plate and using adipose-derived stem cells (ADSCs) and bone morphogenetic protein-2 (BMP-2) to treat femoral head epiphyseal ischemic necrosis, which can be done in juvenile rabbits. Passagefour bromodeoxyuridine (BrdU)-labeled ADSCs were cultured, assayed with MTT to determine their viability and stained with alizarin red dye to determine their osteogenic ability. Two-month-old, healthy male rabbits (1.2 to 1.4 kg, n=45) underwent ischemic induction and were randomly divided into five groups (group A: animal model control; group B: drilling; group C: drilling & ADSCs; group D: drilling & BMP-2; and group E: drilling & ADSCs & BMP-2). Magnetic resonance imaging (MRI), X-ray imaging, hematoxylin and eosin staining and BrdU immunofluorescence detection were applied 4, 6 and 10 weeks after treatment. Approximately 90% of the ADSCs were labeled with BrdU and showed good viability and osteogenic ability. Similar results were observed in the rabbits in groups C and E at weeks 6 and 10. The animals of groups C and E demonstrated normal hip structure and improved femoral epiphyseal quotients and trabecular areas compared with those of the groups A and B (P<0.01). Group D demonstrated improved femoral epiphyseal quotients and trabecular areas compared with those of groups A and B (P<0.05). In summary, drilling through the growth plate combined with ADSC and BMP-2 treatments induced new bone formation and protected the femoral head epiphysis from collapsing in a juvenile rabbit model of femoral head epiphyseal ischemic necrosis.

A long-term follow-up study of the clinical and radiographic outcome of distal trochanteric transfer in Legg-Calvé-Perthes' disease following varus derotational osteotomy

AIMS

To assess the long-term effect of distal trochanteric transfer (DTT) on the clinical and radiographic outcomes of patients with Legg-Calvé-Perthes' disease (LCPD) following a varus derotational osteotomy (VDRO).

PATIENTS AND METHODS

For this single centre cross-sectional retrospective study we analysed the data of 22 patients (24 hips) with LCPD who had greater trochanteric overgrowth (GTO), following a VDRO performed in our institution between 1959 and 1983. GTO was defined as an articular trochanteric distance (ATD) of < 5 mm. We compared the radiographic and clinical outcomes of patients who underwent DTT for GTO (ten patients, ten hips) with those who did not (12 patients, 14 hips). Age at presentation was 6.9 years (4 to 10) and 8.0 years (3.2 to 12) respectively. Symptoms associated with the hip and general quality of life were assessed using the Harris hip score (HHS) and the Short Form (SF)-36 questionnaires.

RESULTS

At long-term follow-up of the DTT group, the ATD was 21.7 mm (standard deviation (sd) 9.8) and the centro-trochanteric distance (CTD) was 13.8 mm (sd 8.3). In the control group the ATD was -0.6 mm (sd 7.8) and the CTD was 32.5 mm (sd 10.2). These differences were statistically significant (p < 0.001). The mean HHS and SF-36 scores were 68.4 (sd 25.0) and 62.0 (sd 27.7) for the DTT group and 73.2 (sd 24.2) and 73.3 (sd 21.5) for the control group, respectively. There was no statistically significant difference in the HHS (p = 0.63) or SF-36 score (p = 0.25). There were four patients who had undergone hip arthroplasty in the DTT group (40%) and one patient (7.1%) in the control group (p = 0.07). The mean age at the time of arthroplasty was 45.3 years (42.1 to 56.5) and 43.6 years respectively. Six patients in the DTT group suffered from moderate to severe osteoarthritis (Tönnis grade 2 or 3) compared with eight patients in the control group (60% versus 57.1%, p = 0.61).

CONCLUSION

Although DTT improved the radiographic results in the long-term follow-up of patients with GTO following VDRO, there was no clinical benefit seen in the HHS, SF-36 or incidence of osteoarthritis compared with patients who had not undergone DTT. Cite this article: Bone Joint J 2017;99-B:987-92.

The physiopathology of avascular necrosis of the femoral head: an update

The physiopathology of the femoral head bone necrosis is similar for children and for adults. The disease is characterized by apoptosis of bone cells - bone marrow and bone forming cells-resulting in head collapse with a subsequent lesion of the overlying cartilage, and therefore flattening of the rounded surface shape of the head articulating with the acetabulum, provoking, eventually, secondary osteoarthritis. When the disease becomes clinically evident already destructive phenomena have occurred and collapse will eventually ensue. In children, because epiphyseal cartilage has growth capabilities, lost epiphyseal height can be recovered, however in adults collapse is irreversible. In this paper the physiopathology of this disease is examined as well as its implication for treatment. Prevention by genetic studies is discussed.