Shelf acetabuloplasty for children with Perthes’ disease and reducible subluxation of the hip

Epidemiology, natural evolution, pathogenesis, clinical spectrum, and management of Legg-Calvé-Perthes

Background

Legg-Calvé-Perthes disease is a self-limiting disorder that develops in children following interruption of the blood supply to the capital femoral epiphysis. This review outlines the current knowledge on the epidemiology, natural evolution, clinical spectrum, and management of the disease.

Methods

The literature pertaining to these aspects of the disease were studied and summarized in this review.

Results

Epidemiological studies suggest that environmental factors contribute to the causation of the disease. Incidence rates monitored over time indicate that the incidence of Legg-Calvé-Perthes disease is declining. The natural evolution followed on sequential plain radiographs enables division of the disease into Stages Ia, Ib, IIa, IIb, IIIa, IIIb, and IV. Reversible deformation of the capital occurs in Stages Ia-IIa simply on standing while irreversible deformation may occur in Stages IIb and IIIa. Treatment of Legg-Calvé-Perthes disease in Stages Ia-IIa aims to prevent the femoral head from getting deformed by containment and avoidance of weight-bearing. In Stages IIb and IIIa, treatment aims to remedy the effects of early irreversible deformation of the femoral head. In Stage IIIb and IV, treatment is directed to correcting the altered shape of the femoral head. The impression that these treatment methods are helpful is based on poor quality evidence.

Conclusion

There is an urgent need to undertake Level I studies to establish the efficacy of currently treatment.

Level of evidence

level V.

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.

Mid–Long-Term Outcomes of Surgical Treatment of Legg-Calvè-Perthes Disease: A Systematic Review

Background: Legg–Calvè–Perthes disease (LCPD) is a common childhood disease that usually occurs in 4- to 12-year-old children. Surgical treatment consists of femoral, pelvic, or combined osteotomies. This comprehensive review aimed to investigate the mid- and long-term outcome of the surgical treatment. Methods: A systematic review of PubMed, Science Direct, and MEDLINE databases was performed by two independent authors, using the keywords “outcome”, “surgical treatment”, “pelvic osteotomy”, “femoral osteotomy”, and “Legg–Calvè–Perthes disease” to evaluate studies of any level of evidence that reported the surgical outcome of LCPD. The result of every stage was reviewed and approved by two senior investigators. Results: A total of 2153 articles were found. At the end of the screening, we selected 23 articles eligible for full-text reading according to the inclusion and exclusion criteria. Our analysis showed that the main prognostic factors for surgical outcome in patients with LCPD are the age at onset and the degree of initial disease severity. Conclusions: Surgical treatment in patients older than 6 years has excellent results in Herring B and B/C hips and poor results in Herring C hips, with a slight advantage for patients between 6 and 8 years old.

Assessing the role of hip arthrography in the treatment decision making for children with Legg-Calvé-Perthes disease

OBJECTIVE

The aim of this study was to determine the role of hip arthrography in the treatment decision making for children with Legg-Calvé-Perthes disease (LCPD).

METHODS

A total of 47 consecutive children with LCPD (42 boys, 5 girls; mean age=7.5 years; range=6-10 years) who underwent operative treatment were included in the study. The patient demographics, physical examination findings (pain and hip range of motion [ROM]), standard anteroposterior and Löwenstein lateral hip radiographs, and hip arthrography data were retrospectively collected. The arthrographies were performed immediately before the surgery under general anesthesia. The patients were staged according to the Catterall and Herring classifications and examined in terms of head-at-risk signs before the study. Four sets of patient files were established based on the aforementioned data, with each child in a randomized and blinded order. Ten consultant pediatric orthopedic surgeons randomly assessed the patient files on 4 separate occasions (Set 1 vs Set 2 and Set 3 vs Set 4), with a minimum time interval of 4 weeks. In the first and second sets, the demographic and clinical information, including the age, gender, hip ROM, and hip radiographs, were presented. In the third and fourth sets, hip arthrography was presented in addition to the data from Set 1 and Set 2. The observers were instructed to choose the best treatment options. The percent agreement (PA) and Gwet's AC1 statistics were used to establish a relative level of agreement among the observers.

RESULTS

The mean intra-observer reliabilities ranged from fair to moderate after adding the hip arthrography data (Gwet's AC1 = 0.36 for Set 1 vs Set 2 and 0.42 for Set 3 vs Set 4). The mean PA was 56.6% (range = 29.8% to 78.7%) with a Gwet's AC1 value of 0.51 (range: 0.21 to 0.77) between Set 1 and Set 3 (moderate intra-observer reliability). The decision for the treatment strategy was changed in 43.4% of the patients. For inter-observer reliability, Gwet's AC1 was computed as 0.48 (moderate reliability). The correlation between the intra-observer reliability and stage progression was not significant (p>0.05) for any of the subgroups. Thus, there is a negative correlation with the disease progression.

CONCLUSION

Hip arthrography seems to have a significant role in the treatment decision making for children with LCPD, especially in the advanced stages of the disease.

LEVEL OF EVIDENCE

Level IV, Therapeutic study.

The Effect of Clinical Knowledge and Surgical Experience on Treatment Choice in Legg-Calve-Perthes Disease: Intra-observer and Inter-observer Reliability Study

AIM

The aim of this study was to evaluate standardized hip radiographs, arthographs, demographic characteristics, physical examination findings, and their effects on treatment choices in leg-calve-perthes disease (LCPD). Intraobserver and interobserver realibility between orthopaedic residents, orthopaedic surgeons, and paediatric orthopaedic surgeons were also investigated.

MATERIALS AND METHODS

47 LCPD patients were included this cross-sectional study. Six separate presentations including different variabilities (clinical findings, standard radiographs, and arthrographs) were evaluated by three different groups (residents, surgeons, paediatric orthopaedic surgeons) and were sent to the observers every other month by hiding patients' personal information. Seven different treatment modalities were introduced for the best treatment modality. Intraobserver and interobserver reliability in these three groups were examined. Percentage aggreement (PA) and intraclass correlation coefficients (ICC) tests were used for this purpose.

RESULTS

Treatment PA rates between presentations were 29.5-53.6% in residents, 38.3-60.4% in surgeons, and 39.1-59.8% in pediatric orthopaedic surgeons. Conservative methods were mostly preferred as treatment modality in all groups; followed by proximal femoral osteotomies. Pediatric orthopaedic surgeons preferred safe dislocation and femur head and/or neck reconstruction surgery 5-18 times more than residents and orthopaedic surgeons. Intraobserver reliability of treatment modalities was higher among the paediatric orthopaedic surgeons; the results were fair-good (0.483-0.763). Among residents and orthopaedic surgeons, ICC values were poor to good, respectively (- 0.080 to 0.636 and 0.263-0.643). Interobserver reliability among three groups was meanly good.

CONCLUSION

As surgical experience increases, both the compliance rates of the treatment modalities and the intra- and inter-group reliability are increased. Knowledge of the demographic data and clinical findings of patients besides hip radiographs or arthrographs increase treatment compliance in paediatric orthopaedic surgeons, however, cause changes in treatment modalities in residents. As surgical experience increases, more difficult surgeries such as safe dislocation and femoral head/neck reconstruction are preferred.

The Pathogenesis and Treatment of Legg-Calvé-Perthes Disease

Legg-Calvé-Perthes disease is a childhood hip condition in which the blood supply to the capital femoral epiphysis is interrupted, causing osteonecrosis and chondronecrosis that lead to progressive deformity of the femoral head and secondary degenerative osteoarthritis in later life. The etiology of Legg-Calvé-Perthes disease remains unclear, with both biological and mechanical factors playing important roles in the pathogenesis of the condition. The treatment of Legg-Calvé-Perthes disease remains controversial but is dependent on several salient factors, including the age at clinical onset, the extent of epiphyseal involvement, the stage of the disease, and the degree of femoral head deformity. The literature supports operative containment treatment in the early stage of disease. Such treatment has led to improved femoral head sphericity with better patient outcomes in multicenter prospective cohort studies. The number of hips that need to be treated operatively in order to achieve a modest treatment effect remains high. Multicenter prospective cohort studies have shown that 6 to 7 patients need to be managed to create 1 spherical femoral head that would not have otherwise occurred.

Percutaneous medial hemi-epiphysiodesis using a transphyseal screw for caput valgum associated with developmental dysplasia of the hip

Background

The purpose of this study was to evaluate the radiologic outcome of percutaneous medial hemi-epiphysiodesis using a transphyseal screw for the management of caput valgum associated with developmental dysplasia of the hip (DDH).

Methods

Eighteen hips (18 patients) having caput valgum treated with screw hemi-epiphysiodesis were followed for more than 2 years, and were included in this study. The mean age at the time of the index operation was 8.3 years (range, 4.3 to 10.7 years) and age at the latest follow-up was 12.2 years (range, 9.4 to 16.4 years). The screw in 5 hips was changed into a longer one at postoperative 21.8 months (range, 14 to 29 months) because the proximal femur outgrew the screw. The screws in 11 hips were removed at the mean age of 10.9 years (range, 8.0 to 14.5 years). We retrospectively analyzed the change in various radiologic parameters over time.

Results

The mean Hilgenreiner-epiphyseal angle (HEA) of the operated side was 5.1 ± 11.3° preoperatively, and increased to 20.6 ± 11.3° at the latest follow-up (p = 0.001). The mean difference of the HEA between the operated and contralateral sides was 16.9 ± 15.1° preoperatively, which decreased to 2.4 ± 12.4° at the latest follow-up (p = 0.008). The mean articulo-trochanteric distance of the operated side, which was 3.2 ± 5.5 mm longer than that of the contralateral side preoperatively, became 5.6 ± 9.1 mm shorter at the latest follow-up (p = 0.001). The ratio of femoral neck length of the operated side to that of the contralateral side decreased over the follow-up period. Acetabular shape as measured by the Sharp angle and acetabular roof angle and femoral head coverage as measured by lateral center-edge angle did not change significantly by the index operation. The ratio of medial joint space width of the operated side to that of the contralateral side did not change significantly.

Conclusions

Screw medial hemi-epiphysiodesis can effectively correct caput valgum associated with DDH. However, this technique remains coxa brevis and does not seem to significantly affect acetabular morphology or reduce subluxation.

The Periosteal Autografts Transplantation for Cartilage Defects of the Hip in Older Children With Developmental Dysplasia as an Adjunctive Procedure

Cartilage lesions are at a high prevalence in dysplastic hips and may relate to arthritic changes and hip joint dysfunction. To date, the effectiveness of repair of articular cartilage defects in the dysplastic hips has not yet been thoroughly evaluated. Here we retrospectively reviewed the effects of acetabuloplasty procedures with/without concomitant autologous tibial periosteal transplantation (ATPT) for articular cartilage defects of the hip in older children with developmental dysplasia of the hip (DDH).Older DDH children with focal cartilage defects of the acetabular or femoral cartilage or both in the hip joint were treated by acetabuloplasty procedures with (Group I) or without (Group II) concomitant ATPT to evaluate the improvements in range of motion (ROM), pain relief of hip, walking tolerability (WL), radiologic evaluations, and outcomes in the long-term follow-up.More satisfactory functional outcome is readily achieved among patients treated with combined acetabuloplasty and ATPT, evidenced by marked pain relief and improved ROM and WL. The latest favorable radiologic evaluation was 70.6% in Group I and 60.0% in Group II, respectively. More hips exhibited congruency between the femoral head and the shell, with less deformity of femoral head and acetabulum or narrowed joint space in Group I. Few major complications were recorded in Group I.Application of periosteal autograft for repair of cartilage defects within the hip joint might be an effective adjunctive treatment for acetabuloplasty in preventing stiffness, reducing pain, and improving ROM and outcomes in hip rehabilitation in the long-term follow-up in older children with DDH.

Early outcomes of one-stage combined osteotomy in Legg-Calve´-Perthes disease

BACKGROUND

Legg-Calve´-Perthes disease (LCPD) is an idiopathic avascular necrosis of the femoral head. There are multiple approaches to the treatment of LCPD ranging from conservative management to a wide variety of surgical methods. Conservative management necessitates extreme degrees of abduction in an orthosis for a longer period of time which further jeopardize capital femoral head vascularity. Surgical containment methods are used in cases where it is desirable. Initial surgical containment methods are varus or varus-derotational osteotomy of the proximal femur or an innominate osteotomy as described by Salter and other pelvic osteotomies. The purpose of this study was to describe the early results of containment methods by one-stage combined osteotomy (femoral varus osteotomy and Salter innominate osteotomy) in patients with severe LCPD.

MATERIALS AND METHODS

23 children were operated in the age group of 4-9 years for LCPD by one-stage combined osteotomy procedure between January 2005 and June 2012. There were 19 boys and 4 girls, left hip involved in 10 cases and right in 13 cases. Preoperatively, they were classified according to Catterall, Joseph's stage and lateral pillar (LP) classification. Postoperatively, clinical results were evaluated in accordance with Ratliff classification and radiological assessment was made by Mose's index, modified Stulberg classification and Epiphyseal extrusion index.

RESULTS

Seventeen hips were Catterall group III, 6 in group IV and all had two or more "head-at-risk" signs. There were 2 patients with stage IIA, 15 were in stage IIB and 6 were in stage IIIA as classified by Joseph's stage of disease. According to LP classification, 11 patients were group B, 3 were group B/C and 9 were in group C. At an average followup of 5.4 years (range 2-9.5 years), the clinical results were good in 12, fair in 9 and poor in 2. According to Mose scale, 8 patients had good results, 13 fair results and 2 had poor results. Based on modified Stulberg classification, there were 10 patients in group A, 11 in group B and 2 in group C. The average preoperative extrusion index was 23.6% which improved postoperatively to 9.5% at latest followup.

CONCLUSIONS

The surgical treatment of LCPD with the best expected outcome is still a challenge. Advanced containment methods by one-stage combined osteotomy can be considered as an alternative treatment where femoral head subluxation or deformity which makes containment difficult or impossible by more conventional methods.

Outcomes of Combined Shelf Acetabuloplasty with Femoral Varus Osteotomy in Severe Legg-Calve-Perthes (LCP) Disease: Advanced Containment Method for Severe LCP Disease

BACKGROUND

Standard treatments may provide adequate containment in mild to moderate Legg-Calve-Perthes disease (LCPD), but they can be problematic in more severe cases. The purpose of this study was to report the results of combined shelf acetabuloplasty with femoral varus osteotomy in severe LCPD.

METHODS

We reviewed 12 patients who had undergone combined shelf acetabuloplasty with femoral varus osteotomy. The indications for this type of operation were: (1) above 8 years of age at clinical onset; (2) massive femoral epiphysis involvement (Catterall group 4, lateral pillar C); (3) femoral head lateral subluxation on the anteroposterior radiograph; and (4) impending hinged abduction on preoperative magnetic resonance imaging or arthrography. The mean age was 9.3 years (range, 8 to 10.8 years). The patients were clinically evaluated with Iowa hip score and leg length discrepancy at the final follow-up. Radiographic outcome was assessed using the Stulberg classification to evaluate femoral head sphericity. The presence of osteoarthritis was evaluated by the Tonnis classification. Correlation analysis was conducted to analyze the preoperative factors that were strongly associated with patients' outcomes.

RESULTS

The mean follow-up period was 10.1 years (range, 7.1 to 13.2 years). Functional grade was excellent in all patients at last follow-up (mean, 92; range, 82 to 99). The mean leg length discrepancy after skeletal maturity was 0.9 cm (range, 0 to 1.7 cm). There were no significant complications or need for additional surgery. Radiographically, 92% of patients reached satisfactory outcomes: Stulberg grade I, 0 cases; Stulberg grade II, 4 cases (34%); Stulberg III, 7 cases (58%), Stulberg IV, 1 case (8%); and Stulberg V, 0 cases. There was no osteoarthritis by Tonnis classification.

CONCLUSIONS

The surgical outcomes for combined shelf acetabuloplasty with femoral varus osteotomy in severe LCPD patients over 8 years old are comparable with other advanced surgical methods. In the cases of severe disease that match our inclusion criteria, our containment method could be another treatment option.

Current perspectives on the pediatric hip: selected topics in hip dysplasia, Perthes disease, and chondrolysis: synopsis of the hip subspecialty session at the POSNA Annual Meeting, May 1, 2013, Toronto

The following are proceedings from the Hip Breakout Session held at the 2013 annual meeting of the Pediatric Orthopaedic Society of North America in Toronto, Canada. The organizer's goal of the meeting was to gather experts with years of clinical experience to discuss topics based upon both experience and current clinical evidence. The topics that were selected represented the most commonly encountered pathology where there are wide variations of clinical practice. The invited speakers were asked to summarize both their clinical experience and the current scientific evidence and to summarize areas that require further scientific investigation.

Orthopaedic manifestations and treatment outcome of two siblings with Escobar syndrome and homozygous mutations in the CHRNG gene

Escobar syndrome is a nonlethal subtype of multiple pterygium syndromes, characterized by webbing across the joints, congenital joint contracture, facial dysmorphism and a variety of other congenital anomalies. We report orthopaedic manifestation and the treatment outcome of two siblings with Escobar syndrome caused by homozygous mutations of the CHRNG gene.

Shelf acetabuloplasty for containment in the early stages of Legg-Calve-Perthes disease

BACKGROUND

To evaluate the effectiveness of shelf acetabuloplasty in the containment of extruded hips without hinge abduction in early stages of Legg-Calve-Perthes disease, we present a retrospective series of 44 patients (45 hips) treated between August 1999 and February 2010, which included 34 boys and 10 girls with a mean age at diagnosis of 7.4 years (range, 3.9 to 15.3).

METHODS

All patients presented with sclerosis or early fragmentation stages. The average time from diagnosis to surgery was 2.1 months (range, 0 to 8.2) and the mean time to heal was 40.4 months (range, 20 to 82.2). The Reimer migration and the deformity indices were measured on initial, preoperative, postoperative, and healed x-rays. The average deformity index at 3 of those 4 timepoints was significantly related to their final Stulberg classification. CE angles increased and Sharp angles decreased significantly as a result of treatment.

RESULTS

At the healed stage and consistent with other published series, 84.4% of patients were Stulberg III or less, denying any pain, and with full range of movement, whereas 15.6% were classified as Stulberg IV.

CONCLUSIONS

We defend that shelf acetabuloplasty should be performed early in the disease and, uniquely, we propose that the indication for treatment should be guided by the deformity and the Reimer migration indices.

LEVEL OF EVIDENCE

IV.

The use of arthrography in pediatric orthopaedic surgery

Surgery near pediatric joints can be challenging because it is difficult to visualize vital articular structures. Assessment of underlying pathology is also challenging because the joint structures have not yet ossified. Arthrography is a useful tool that is quick and minimally invasive and allows adequate visualization of joint anatomy during surgery, which aids intraoperative decision making. In pediatric patients, arthrography is most useful for visualization of the elbow, knee, and hip joints. This tool can help the surgeon to refine the diagnosis and management of pediatric fractures and aids in surgical assessment during joint and limb reconstruction. Arthrography adds minimal time to surgery and carries a low risk of complications; it should be part of the armamentarium of any surgeon who treats pediatric orthopaedic patients.

Shelf acetabuloplasty in the treatment of severe Legg-Calvé-Perthes disease: good outcomes at midterm follow-up

The aim of the study was to retrospectively review results of operative treatment for coverage deficit of femoral head in children with severe epiphysis displacement in Legg-Calvé-Perthes (LCP) disease. The material included 23 shelf acetabuloplasty procedures for LCP disease. The average age at diagnosis was 8.1 years (range 4–12). Mean follow-up was 5.8 years (range from 2.2 to 11.2 years). Mean Reimer's index decreased statistically significantly from a mean of 32% before surgery to 10.0% at the last follow-up (P < 0.00001). The mean Wiberg center-edge angle increased also statistically significantly from a mean of 17.3° before procedure to 32.3° at the last follow-up (P < 0.00001). According to the Stulberg classification, type I was observed in 2, type II in 13, type III in 6, and type IV in 2 hips. There were no differences in the range of motion or leg length discrepancy in preoperative and postoperative standing. Partial, not significant, bone graft resorption was noted in 6 cases in the first 6–9 months after surgery. To conclude, shelf acetabuloplasty allows achieving good midterm results in the treatment of severe stages of LCP disease. The procedure improves coverage of femoral head and allows its remodelling.

Perthes disease: evaluation and management

Perthes disease refers to self-limiting idiopathic avascular necrosis of capital femoral epiphysis in a child. There is no consensus for the optimum treatment of Perthes disease even 100 years after the first description. The prime aim of the treatment is to maintain the sphericity of the femoral head and the congruency of the femur-acetabulum relationship to prevent secondary degenerative arthritis. Early diagnosis and management can help the collapse of femoral head, progressive femoral head deformity, and impingement.

The role of shelf acetabuloplasty in early and late stages of Perthes disease: a meta-analysis of observational studies

PURPOSE

Perthes disease may result in deformity of the proximal femoral epiphysis and incongruity of the hip, and shelf acetabuloplasty has been frequently used for treatment. The aim of this study was to review the published articles about the outcome of shelf acetabuloplasty as a containment or reconstruction-salvage procedure in Perthes disease.

METHODS

We utilized the PubMed online database for peer review articles using the following search terms: shelf arthroplasty, acetabuloplasty, and Perthes. To be included in this meta-analysis, we isolated studies on children with Perthes disease who received shelf acetabuloplasty as a treatment, conducted in any geographic location with the Stulberg classification outcome. Twenty articles were identified for a qualitative systematic review. The fixed effect and random effect meta-analysis were performed as appropriate for the summary pool estimate following the heterogeneity test. The meta-analysis was performed on 11 articles in three categories: all articles, articles for shelf arthroplasty in the early stages of Perthes disease, and in the late stages.

RESULTS

Overall, shelf acetabuloplasty provided 84 % good outcome of Stulberg classes I, II, and III. Shelf acetabuloplasty performed in early stages for containment provided good outcome in 85 %, while only 69 % good outcome was achieved when shelf acetabuloplasty was performed in late stages for reconstruction-salvage.

CONCLUSION

Shelf acetabuloplasty provides a good or fair Stulberg outcome when performed in early Perthes stages (Waldenström stages I and II) as a containment surgery, but less favorable outcomes were observed when shelf surgery was used for reconstructive-salvage purposes in late Perthes disease stages (Waldenström stages III and IV). Caution is advised in performing the shelf procedure in children over 10-11 years of age.

What is the evidence supporting the prevention of osteoarthritis and improved femoral coverage after shelf procedure for Legg-Calvé-Perthes disease?

BACKGROUND

The evidence supporting continued use of shelf acetabuloplasty in Legg-Calvé-Perthes disease (LCPD) is not well-defined, and there is controversy regarding the long-term benefits related to clinical and functional improvement.

QUESTIONS/PURPOSES

Our goals were to determine whether shelf arthroplasty for LCPD (1) prevents the onset of early osteoarthritis; (2) improves pain, ROM, activity, and functional outcomes; (3) maintains or improves femoral head containment, sphericity, and congruency; (4) changes the acetabular index; and (5) is associated with a low rate of complications.

METHODS

We performed a systematic review of the medical literature from 1966 to 2009 using the search terms Perthes, shelf procedure, and acetabuloplasty. We excluded reports using multiple/combined treatment methods and those not clearly stratifying outcomes. Thirteen studies met the criteria. There were no Level I studies, one Level II prognostic study, five Level III therapeutic studies, and seven Level IV studies. Mean followup ranged from 2.6 to 17.9 years.

RESULTS

Only one study reported progression to early osteoarthritis in one patient. We found no evidence for improvement in ROM and continued pain relief at long-term followup. Mean decrease in lateral subluxation ratio was 13% to 30%, demonstrating an improvement in femoral head containment. Mean acetabular cover percentage improved 16% to 38%, and mean acetabular and center-edge angles improved 4° to 14° and 8° to 33°, respectively. There were no reports of any major complications after the procedure.

CONCLUSIONS

While radiographic measurements indicate improved coverage of the femoral head after shelf acetabuloplasty for LCPD, available evidence does not document the procedure prevents early onset of osteoarthritis or improves long-term function.

Does shelf acetabuloplasty influence acetabular growth and remodeling?

BACKGROUND

Shelf acetabuloplasty has the potential to cause iatrogenic acetabular growth arrest, although accelerated acetabular growth has been reported based on plain radiographic evaluations in patients with Legg-Calvé-Perthes disease. Because plain radiographs may be limited in depicting actual acetabular morphology, it is unclear whether there are growth disturbances.

QUESTIONS/PURPOSES

We therefore determined (1) whether focal or generalized acetabular growth stimulation or retardation occurred based on CT analysis in combination with plain radiographic assessment; and (2) whether radiographically assessed femoral head deformity, subluxation, and acetabular dysplasia were associated with residual zonal rim dysplasia of the acetabulum.

METHODS

We examined 14 patients who had undergone shelf acetabuloplasty for "reducible subluxation" and underwent CT scans at a mean 7 years after surgery (range, 3-11 years). We measured radiographic indices reflecting acetabular depth and rim dysplasia on multiplanar reformatted images in 10 radial planes and on plain radiographs and calculated their operation-to-control ratios to assess growth changes. The mean age at surgery was 9.3 years (range, 7-12 years).

RESULTS

We observed generalized accelerated growth in 11 hips and equivocal growth in three. None of the 14 hips showed an abrupt change in acetabular geometry. Despite improved acetabular depth in all hips, eight hips had focal rim dysplasia in the superior zone on CT examinations, and this was associated with a smaller center-edge angle, a greater deformity index, and preexisting acetabular dysplasia.

CONCLUSIONS

Our observations support the notion that shelf acetabuloplasty has a favorable, stimulatory effect on acetabular growth. However, the possible persistence of preexisting zonal rim dysplasia should be considered.

Core decompression for juvenile osteonecrosis

Core decompression may be used as adjunct for treatment in some cases of Legg-Calvé-Perthes disease (LCPD). The primary application is for patients with onset at 12 years of age or older. We recommend classifying these older patients as idiopathic juvenile osteonecrosis and treating them similarly to adults with avascular necrosis. Juvenile osteonecrosis may benefit from core decompression combined with shelf acetabuloplasty during the early stages of necrosis. Younger children with LCPD may benefit from decompression by fenestration of the femoral head. Experience in adult-onset osteonecrosis and our early experience suggest that some patients may benefit from these adjunctive treatments.

Shelf and/or reduction and containment surgery

Hinge abduction occurs early in the fragmentation stage of Legg-Calvé-Perthes disease and should be suspected when abduction and internal rotation are lost. It can be confirmed by an AP radiograph in abduction and internal rotation in which the ossific nucleus is not covered by the acetabulum. An arthrogram can then yield greater information regarding the reversibility of the hinge abduction. Hinge abduction should be considered a contraindication to containment by redirectional pelvic or femoral varus osteotomy. However, good results have been reported with acetabular augmentation via shelf procedures or Chiari osteotomies. Valgus femoral osteotomies have also been beneficial in the treatment of the Legg-Calvé-Perthes hip with hinge abduction.

Principles of treatment in late stages of Perthes disease

It is of paramount importance to distinguish hips that may or may not be suitable for containment in the transitional stage (fragmentation to early reossification stage), because long-term clinical and radiological outcomes may be influenced by the choice of treatment. This article summarizes the definition of hinge abduction, pathoanatomy of hinge segment, assessment of hinge abduction, determination of reducible and irreducible hinge abduction, and treatment strategies for containable and uncontainable hips in the transitional stage.

Containment methods for treatment of Legg-Calvé-Perthes disease

The objective of containment treatment in Perthes disease is to hold the femoral head in the acetabulum during the period of "biologic plasticity" while necrotic bone is resorbed and living bone is restored through the process of "creeping substitution." This article identifies the various methods of containment and the technical aspects of each method. Choice of method depends on the experience of the surgeon and the psychosocial needs of the patient and family. Failure is more commonly a result of inappropriate patient selection for a particular method, delay in management, or technical errors rather than to the method that was selected.

Degenerative osteoarthritis after Perthes' disease: a 36-year follow-up

BACKGROUND

Although the prognosis of Perthes' disease at skeletal maturity is considered favorable, little is known about the long-term results after middle age.

METHODS

We retrospectively analyzed the radiographic and functional outcomes of 67 patients (70 hips) who had been treated for Perthes' disease. Of these patients, 28 patients (29 hips) were evaluated using JOA (Japanese Orthopaedic Association) score and radiographs at follow-up (Group 1), 39 patients (41 hips) were evaluated by a postal questionnaire (Group 2). The mean follow-up period was 36.1 years. The mean age at follow-up was 43.1 years.

RESULTS

Group 1, good radiographic results (Stulberg class I or II) were achieved in 59% of hips. No osteoarthritis (Tönnis Grade 0) was observed in only 48% of hips. The clinical results were good (JOA score ≥ 70) in 79% of hips. Disturbance of walking ability and activities of daily living was little. The Tönnis grade and JOA score declined after 40 years of age. All patients older than 50 years showed severe osteoarthritis. The severity of osteoarthritis correlated significantly with age at follow-up. Group 2, the clinical results were good (JOA score ≥ 56) in 76% of hips. In both groups, no patient had undergone total hip arthroplasty. Younger age at diagnosis (<8 years) correlated significantly with a better result. The JOA score correlated significantly with age at follow-up.

CONCLUSION

Patients who were treated for Perthes' disease have a risk of osteoarthritis and a clinically poor outcome after the age of 40-50 years.