Aims. The paediatric trigger thumb is a distinct clinical entity with unique anatomical abnormalities. The aim of this study was to present the long-term outcomes of A1 pulley release in idiopathic paediatric trigger thumbs based on established patient-reported outcome measures. Methods. This study was a cross-sectional, questionnaire-based study conducted at a tertiary care orthopaedic centre. All cases of idiopathic paediatric trigger thumbs which underwent A1 pulley release between 2004 and 2011 and had a minimum follow-up period of ten years were included in the study. The abbreviated version of the Disabilities of Arm, Shoulder and Hand questionnaire (QuickDASH) was administered as an online survey, and ipsi- and contralateral thumb motion was assessed. Results. A total of 67 patients completed the survey, of whom 63 (94%) had full interphalangeal joint extension or hyperextension. Severe metacarpophalangeal joint hyperextension (> 40°) was documented in 15 cases (22%). The median QuickDASH score was 0 (0 to 61), indicating excellent function at a median follow-up of 15 years (10 to 19). Overall satisfaction was high, with 56 patients (84%) reporting the maximal satisfaction score of 5. Among 37 patients who underwent surgery at age ≤ two years, 34 (92%) reported the largest satisfaction, whereas this was the case for 22 of 30 patients (73%) with surgery at aged > two years (p = 0.053). Notta’s nodule resolved in 49 patients (73%) at final follow-up. No residual triggering or revision surgery was observed. Conclusion. Surgical release of A1 pulley in paediatric trigger thumb is an acceptable procedure with excellent functional long-term outcomes. There was a trend towards higher satisfaction with earlier surgery among the patients. Cite this article: Bone Jt Open 2024;5(9):736–741

Aims. We aimed to assess the cumulative risk of total hip arthroplasty (THA) from in situ fixation for slipped capital femoral epiphysis (SCFE) after a follow-up of almost 50 years. Methods. In this study, 138 patients with 172 affected hips treated with in situ fixation were evaluated retrospectively. A total of 97 patients (70%) were male and the mean age was 13.6 years (SD 2.1); 35 patients (25%) had a bilateral disease. The median follow-up time was 49 years (interquartile range 43 to 55). Basic demographic, stability, and surgical details were obtained from patient records. Preoperative radiographs (slip angle; SA) were measured, and data on THA was gathered from the Finnish National Arthroplasty Register. Results. The preoperative SA was a mean of 39° (SD 19°). At follow-up, 56 of the patients had undergone THA for a hip previously fixed in situ for SCFE (41%) and 64 of all affected hips had been replaced (37%). Kaplan-Meier analysis gave a median prosthesis-free postoperative survival of 55 years (95% confidence interval (CI) 45 to 64) for the affected hips. In a multivariate analysis, female patients had a two-fold risk for THA (hazard ratio (HR) 2.42 (95% CI 1.16 to 5.07)) and a greater preoperative SA increased the risk of THA (HR 1.03 for every increment of 1° (95% CI 1.01 to 1.05)), while patient age at surgery, slip laterality, stability of slip, or diagnostic delay did not have a statistically significant effect on the risk of THA. Conclusion. SCFE treated primarily with in situ fixation may lead to THA in more than 40% of affected hips at a near 50-year follow-up. This risk is approximately 15-times the reported lifetime risk in the Finnish general population. Female sex and increasing preoperative SA significantly predicted higher risk of THA. Cite this article: Bone Joint J 2023;105-B(12):1321–1326

We present the long term outcome from children with Legg-Calves-Perthes (LCPD) treated at our unit. Patients treated for LCPD were identified retrospectively from an orthopaedic database between 1990 and 2005. Patient demographics, clinical examination, treatment and Herring classification were recorded at initial presentation and treatment. Long-term clinical and radiological follow-up was also recorded. 85 patients were identified and 4 excluded due to insufficient data giving a total of 81 patients. Of these, 58 were male and 23 female. Average age range at presentation was 6.5 years (range 1.5–14 yrs). The side affected was 34 right, 35 left, 24 bilateral giving 93 hips in total. Time between presentation and diagnosis averaged 4.7 months (range 0–48 months). In patients with recorded clinical examination 87% had reduced abduction and 88% reduced internal rotation. Treatment was largely conservative with 12 hips (13%) undergoing surgery within the first 4 years of diagnosis. Radiographs were available for 71 hips. Herring classification was A-12, B-22, C-37. Long term follow up averaged 16 years (range 10–25 yrs). Stulberg grading was available in 67 hips; Grade I 13, Grade II 21, Grade III 19, Grade IV 18 and Grade V 6. There were ongoing issues (mostly pain) in 18 hips, 5 of which required a subsequent operation. No correlation was found between abduction and Stulberg grade (p-value = 0.7). A correlation was found between delay in diagnosis of ≥6 months and the need for a subsequent operation (p-value = 0.0408). The overall trend as expected showed that a better Herring classification generally led to a more favourable Stulberg classification. Range of motion was not predictive for Stulberg grade. The need for further surgical intervention for symptoms at long term follow up was 0.05%

The practice of regular radiological follow-up of infants with a positive family history of developmental dysplasia of the hip is based on the widespread belief that primary acetabular dysplasia is a genetic disorder which can occur in the absence of frank subluxation or dislocation. We reviewed all infants who were involved in our screening programme for developmental dysplasia of the hip, between November 2002 and January 2004, and who had a normal clinical and ultrasound examination of the hip at six to eight weeks of age, but who, because of a family history of developmental dysplasia of the hip, had undergone further radiography after an interval of 6 to 12 months. The radiographs of 89 infants were analysed for signs of late dysplasia of the hip and assessed independently by three observers to allow for variability of measurement. There were 11 infants (11%) lost to follow-up. All the patients had normal radiographs at the final follow-up and none required any intervention. We therefore question the need for routine radiological follow-up of infants with a positive family history of developmental dysplasia of the hip, but who are normal on clinical examination and assessment by ultrasound screening when six to eight weeks old

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 treatment of developmental dysplasia of the hip (DDH) in children remains controversial, we describe the clinical and radiological outcomes of 47 hips in 43 children treated with open surgery by one surgeon between 2004 and 2008 for DDH.

The mean age at operation was 25 months (5 to 113) with a mean follow up of 89 months (22 to 169).

46 hips had an anterior open reduction, 1 had a medial approach performed and 16 had anterior open reductions only. 5 of the primary operations also had a pelvic osteotomy, 7 had a femoral osteotomy and 18 had a combined femoral and pelvic osteotomy.

7 (15%) of the hips required a second operation for dislocation, subluxation or dysplasia.

At the latest follow up 40 of the 45 hips where Severin grades were recordable (89%) were graded as excellent or good, Severin class I or II. Clinically significant AVN (grade II to III according to the Kalamchi and MacEwen classification) was seen in 5 (11%) of the hips.

We found a pelvic osteotomy to be a risk factor for AVN (p 0.02) and age at operation to be a risk factor for poor morphology at final follow up (p 0.03).

We proceed to open surgery in patients over 12 months old or those with failed closed reduction. Over 18 months old a pelvic osteotomy should be performed in selective cases depending on intra-operative stability, but we will now consider doing this as a staged procedure and delaying the osteotomy for a period of time after open reduction to reduce the risk of AVN. We will also have a much lower threshold for performing a femoral shortening osteotomy in these patients as open reduction with Salters osteotomy alone tended to have a poorer outcome.

Aims. Radiological residual acetabular dysplasia (RAD) has been reported in up to 30% of children who had successful brace treatment of infant developmental dysplasia of the hip (DDH). Predicting those who will resolve and those who may need corrective surgery is important to optimize follow-up protocols. In this study we have aimed to identify the prevalence and predictors of RAD at two years and five years post-bracing. Methods. This was a single-centre, prospective longitudinal cohort study of infants with DDH managed using a published, standardized Pavlik harness protocol between January 2012 and December 2016. RAD was measured at two years’ mean follow-up using acetabular index-lateral edge (AI-L) and acetabular index-sourcil (AI-S), and at five years using AI-L, AI-S, centre-edge angle (CEA), and acetabular depth ratio (ADR). Each hip was classified based on published normative values for normal, borderline (1 to 2 standard deviations (SDs)), or dysplastic (> 2 SDs) based on sex, age, and laterality. Results. Of 202 infants who completed the protocol, 181 (90%) had two and five years’ follow-up radiographs. At two years, in 304 initially pathological hips, the prevalence of RAD (dysplastic) was 10% and RAD (borderline) was 30%. At five years, RAD (dysplastic) decreased to 1% to 3% and RAD (borderline) decreased to < 1% to 2%. On logistic regression, no variables were predictive of RAD at two years. Only AI-L at two years was predictive of RAD at five years (p < 0.001). If both hips were normal at two years’ follow-up (n = 96), all remained normal at five years. In those with bilateral borderline hips at two years (n = 21), only two were borderline at five years, none were dysplastic. In those with either borderline-dysplastic or bilateral dysplasia at two years (n = 26), three (12%) were dysplastic at five years. Conclusion. The majority of patients with RAD at two years post-brace treatment, spontaneously resolved by five years. Therefore, children with normal radiographs at two years post-brace treatment can be discharged. Targeted follow-up for those with abnormal AI-L at two years will identify the few who may benefit from surgical correction at five years’ follow-up. Cite this article: Bone Joint J 2024;106-B(7):744–750

Aims. Multiple secondary surgical procedures of the shoulder, such as soft-tissue releases, tendon transfers, and osteotomies, are described in brachial plexus birth palsy (BPBP) patients. The long-term functional outcomes of these procedures described in the literature are inconclusive. We aimed to analyze the literature looking for a consensus on treatment options. Methods. A systematic literature search in healthcare databases (PubMed, Embase, the Cochrane library, CINAHL, and Web of Science) was performed from January 2000 to July 2020, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. The quality of the included studies was assessed with the Cochrane ROBINS-I risk of bias tool. Relevant trials studying BPBP with at least five years of follow-up and describing functional outcome were included. Results. Of 5,941 studies, 19 were included after full-text screening. A total of 15 surgical techniques were described. All studies described an improvement in active external rotation (range 12° to 128°). A decrease in range of motion and Mallet score after long-term (five to 30 years) follow-up compared to short-term follow-up was seen in most studies. Conclusion. The literature reveals that functional outcome increases after different secondary procedures, even in the long term. Due to the poor methodological quality of the included studies and the variations in indication for surgery and surgical techniques described, a consensus on the long-term functional outcome after secondary surgical procedures in BPBP patients cannot be made. Cite this article: Bone Joint J 2023;105-B(4):455–464

Aims. Fixation techniques used in the treatment of slipped capital femoral epiphysis (SCFE) that allow continued growth of the femoral neck, rather than inducing epiphyseal fusion in situ, have the advantage of allowing remodelling of the deformity. The aims of this study were threefold: to assess whether the Free-Gliding (FG) SCFE screw prevents further slip; to establish whether, in practice, it enables lengthening and gliding; and to determine whether the age of the patient influences the extent of glide. Methods. All patients with SCFE who underwent fixation using FG SCFE screws after its introduction at our institution, with minimum three years’ follow-up, were reviewed retrospectively as part of ongoing governance. All pre- and postoperative radiographs were evaluated. The demographics of the patients, the grade of slip, the extent of lengthening of the barrel of the screw and the restoration of Klein’s line were recorded. Subanalysis was performed according to sex and age. Results. A total of 19 hips in 13 patients were included. The mean age of the patients at the time of surgery was 11.5 years (9 to 13) and the mean follow-up was 63 months (45 to 83). A total of 13 FG SCFE screws were used for the fixation of mild or moderate SCFE, with six contralateral prophylactic fixations. No hip with SCFE showed a further slip after fixation and there were no complications. Lengthening occurred in 15 hips (79%), with a mean lengthening of the barrel of 6.8 mm (2.5 to 13.6) at final follow-up. Remodelling occurred in all hips with lengthening of the barrel. There was statistically more lengthening in patients who were aged < 12 years, regardless of sex (p = 0.002). Conclusion. The FG SCFE screw is effective in preventing further slip in patients with SCFE. Lengthening of the barrel occurred in most hips, and thus allowed remodelling. This was most marked in younger children, regardless of sex. Based on this study, this device should be considered for use in patients with SCFE aged < 12 years instead of standard pinning in situ. Cite this article: Bone Joint J 2023;105-B(2):215–219

Aims. To examine the long-term outcome of arthrodesis of the hip undertaken in a paediatric population in treating painful arthritis of the hip. In our patient population, most of whom live rurally in hilly terrain and have limited healthcare access and resources, hip arthrodesis has been an important surgical option for the monoarticular painful hip in a child. Methods. A follow-up investigation was undertaken on a cohort of 28 children previously reported at a mean of 4.8 years. The present study looked at 26 patients who had an arthrodesis of the hip as a child at a mean follow-up of 20 years (15 to 29). Results. The mean Harris Hip Score (HHS) increased from 39.60 (SD 11.06) preoperatively to 81.02 (SD 8.86; p = 0.041) at final review. At latest follow-up, the HHS was found to be excellent in four patients (15%), good in 11 (42%), and fair in 11 (42%). A total of 16 patients (62%) reported mild low back pain, five (19%) had moderate pain, and five (19%) patients had no back pain. Mild ipsilateral knee pain was reported by 19 (73%), moderate pain by one (4%), and no pain by six (23%) patients. Mild contralateral hip pain was reported by ten patients (38%), and no pain by 16 (62%). The 36-Item Short Form Health Survey scores were very good in four patients (15%), good in 18 (70%), and poor in four (15%), with a mean score of 70.92 (SD 12.65). Of 13 female patients who had given birth, 12 did so with uncomplicated vaginal delivery. All patients had to modify their posture for toileting, putting on lower body clothes, foot care, and putting on shoes. Conclusion. Our results show that with hip arthrodesis, most patients have relatively good function at long-term follow-up, although some pain is experienced in adjacent joints, and modification in some activities of daily living is common. Cite this article: Bone Joint J 2022;104-B(9):1089–1094

Aims. The gold standard for percutaneous Achilles tendon tenotomy during the Ponseti treatment for idiopathic clubfoot is a tenotomy with a No. 15 blade. This trial aims to establish the technique where the tenotomy is performed with a large-bore needle as noninferior to the gold standard. Methods. We randomized feet from children aged below 36 months with idiopathic clubfoot on a 1:1 basis in either the blade or needle group. Follow-up was conducted at three weeks and three months postoperatively, where dorsiflexion range, Pirani scores, and complications were recorded. The noninferiority margin was set at 4° difference in dorsiflexion range at three months postoperatively. Results. The blade group had more dorsiflexion at both follow-up consultations: 18.36° versus 18.03° (p = 0.115) at three weeks and 18.96° versus 18.26° (p = 0.001) at three months. The difference of the mean at three months 0.7° is well below the noninferiority margin of 4°. There was no significant difference in Pirani scores. The blade group had more extensive scar marks at three months than the needle group (8 vs 2). No major complications were recorded. Conclusion. The needle tenotomy is noninferior to the blade tenotomy for usage in Ponseti treatment for idiopathic clubfoot in children aged below 36 months. Cite this article: Bone Joint J 2024;106-B(8):871–878

Aims. The present study seeks to investigate the correlation of pubofemoral distances (PFD) to α angles, and hip displaceability status, defined as femoral head coverage (FHC) or FHC during manual provocation of the newborn hip < 50%. Methods. We retrospectively included all newborns referred for ultrasound screening at our institution based on primary risk factor, clinical, and PFD screening. α angles, PFD, FHC, and FHC at follow-up ultrasound for referred newborns were measured and compared using scatter plots, linear regression, paired t-test, and box-plots. Results. We included 2,735 newborns, of whom 754 received a follow-up hip ultrasound within six weeks of age. After exclusion, 1,500 hips were included for analysis. Sex distribution was 372 male and 380 female, and the mean age at examination was 36.6 days (4 to 87). We found a negative linear correlation of PFD to α angles (p < 0.001), FHC (p < 0.001), and FHC during provocation (p < 0.001) with a 1 mm increase in PFD corresponding to a -2.1° (95% confidence interval (CI) -2.3 to -1.9) change in α angle and a -3.4% (95% CI -3.7 to -3.0) change in FHC and a -6.0% (-6.6 to -5.5) change in FHC during provocation. The PFD was significantly higher with increasing Graf types and in displaceable hips (p < 0.001). Conclusion. PFD is strongly correlated to both α angles and hip displaceability, as measured by FHC and FHC during provocation, in ultrasound of newborn hips. The PFD increases as the hips become more dysplastic and/or displaceable. Cite this article: Bone Jt Open 2023;5(1):3–8

Aims. There is a lack of high-quality research investigating outcomes of Ponseti-treated idiopathic clubfeet and correlation with relapse. This study assessed clinical and quality of life (QoL) outcomes using a standardized core outcome set (COS), comparing children with and without relapse. Methods. A total of 11 international centres participated in this institutional review board-approved observational study. Data including demographics, information regarding presentation, treatment, and details of subsequent relapse and management were collected between 1 June 2022 and 30 June 2023 from consecutive clinic patients who had a minimum five-year follow-up. The clubfoot COS incorporating 31 parameters was used. A regression model assessed relationships between baseline variables and outcomes (clinical/QoL). Results. Overall, 293 patients (432 feet) with a median age of 89 months (interquartile range 72 to 113) were included. The relapse rate was 37%, with repeated relapse in 14%. Treatment considered a standard part of the Ponseti journey (recasting, repeat tenotomy, and tibialis anterior tendon transfer) was performed in 35% of cases, with soft-tissue release and osteotomies in 5% and 2% of cases, respectively. Predictors of relapse included duration of follow-up, higher initial Pirani score, and poor Evertor muscle activity. Relapse was associated with poorer outcomes. Conclusion. This is the first multicentre study using a standardized COS following clubfoot treatment. It distinguishes patients with and without relapse in terms of clinical outcomes and QoL, with poorer outcomes in the relapse group. This tool allows comparison of treatment methods and outcomes, facilitates information sharing, and sets family expectations. Predictors of relapse encourage us to create appropriate treatment pathways to reduce relapse and improve outcome. Cite this article: Bone Joint J 2024;106-B(7):735–743

Aims. Brace treatment is the cornerstone of managing developmental dysplasia of the hip (DDH), yet there is a lack of evidence-based treatment protocols, which results in wide variations in practice. To resolve this, we have developed a comprehensive nonoperative treatment protocol conforming to published consensus principles, with well-defined a priori criteria for inclusion and successful treatment. Methods. This was a single-centre, prospective, longitudinal cohort study of a consecutive series of infants with ultrasound-confirmed DDH who underwent a comprehensive nonoperative brace management protocol in a unified multidisciplinary clinic between January 2012 and December 2016 with five-year follow-up radiographs. The radiological outcomes were acetabular index-lateral edge (AI-L), acetabular index-sourcil (AI-S), centre-edge angle (CEA), acetabular depth ratio (ADR), International Hip Dysplasia Institute (IHDI) grade, and evidence of avascular necrosis (AVN). At five years, each hip was classified as normal (< 1 SD), borderline dysplastic (1 to 2 SDs), or dysplastic (> 2 SDs) based on validated radiological norm-referenced values. Results. Of 993 infants assessed clinically and sonographically, 21% (212 infants, 354 abnormal hips) had DDH and were included. Of these, 95% (202 infants, 335 hips) successfully completed bracing, and 5% (ten infants, 19 hips) failed bracing due to irreducible hip(s). The success rate of bracing for unilateral dislocations was 88% (45/51 infants) and for bilateral dislocations 83% (20/24 infants). The femoral nerve palsy rate was 1% (2/212 infants). At five-year follow-up (mean 63 months (SD 5.9; 49 to 83)) the prevalence of residual dysplasia after successful brace treatment was 1.6% (5/312 hips). All hips were IHDI grade I and none had AVN. Four children (4/186; 2%) subsequently underwent surgery for residual dysplasia. Conclusion. Our comprehensive protocol for nonoperative treatment of infant DDH has shown high rates of success and extremely low rates of residual dysplasia at a mean age of five years. Cite this article: Bone Joint J 2023;105-B(8):935–942

Aims. To investigate the risk factors for unsuccessful radial head reduction (RHR) in children with chronic Monteggia fractures (CMFs) treated surgically. Methods. A total of 209 children (mean age 6.84 years (SD 2.87)), who underwent surgical treatment for CMFs between March 2015 and March 2023 at six institutions, were retrospectively reviewed. Assessed risk factors included age, sex, laterality, dislocation direction and distance, preoperative proximal radial metaphysis width, time from injury to surgery, reduction method, annular ligament reconstruction, radiocapitellar joint fixation, ulnar osteotomy, site of ulnar osteotomy, preoperative and postoperative ulnar angulation, ulnar fixation method, progressive ulnar distraction, and postoperative cast immobilization. Independent-samples t-test, chi-squared test, and logistic regression analysis were used to identify the risk factors associated with unsuccessful RHR. Results. Redislocation occurred during surgery in 48 patients (23%), and during follow-up in 44 (21.1%). The mean follow-up of patients with successful RHR was 13.25 months (6 to 78). According to the univariable analysis, time from injury to surgery (p = 0.002) and preoperative dislocation distance (p = 0.042) were identified as potential risk factors for unsuccessful RHR. However, only time from injury to surgery (p = 0.007) was confirmed as a risk factor by logistic regression analysis. Receiver operating characteristic curve analysis and chi-squared test confirmed that a time from injury to surgery greater than 1.75 months increased the rate of unsuccessful RHR above the cutoff (p = 0.002). Conclusion. Time from injury to surgery is the primary independent risk factor for unsuccessful RHR in surgically treated children with CMFs, particularly in those with a time from injury to surgery of more than 1.75 months. No other factors were found to influence the incidence of unsuccessful RHR. Surgical reduction of paediatric CMFs should be performed within the first two months of injury whenever possible. Cite this article: Bone Jt Open 2024;5(7):581–591

Aims. The aim of this study is to evaluate the surgical treatment with the best healing rate for patients with proximal femoral unicameral bone cysts (UBCs) after initial surgery, and to determine which procedure has the lowest adverse event burden during follow-up. Methods. This multicentre retrospective study was conducted in 20 tertiary paediatric hospitals in France, Belgium, and Switzerland, and included patients aged < 16 years admitted for UBC treatment in the proximal femur from January 1995 to December 2017. UBCs were divided into seven groups based on the index treatment, which included elastic stable intramedullary nail (ESIN) insertion with or without percutaneous injection or grafting, percutaneous injection alone, curettage and grafting alone, and insertion of other orthopaedic hardware with or without curettage. Results. A total of 201 patients were included in the study. The mean age at diagnosis was 8.7 years (SD 3.9); 77% (n = 156) were male. The mean follow-up was 9.4 years (SD 3.9). ESIN insertion without complementary procedure had a 67% UBC healing rate after the first operation (vs 30% with percutaneous injection alone (p = 0.027), 43% with curettage and grafting (p = 0.064), and 21% with insertion of other hardware combined with curettage (p < 0.001) or 36% alone (p = 0.014)). ESIN insertion with percutaneous injection presented a 79% healing rate, higher than percutaneous injection alone (p = 0.017), curettage and grafting (p = 0.028), and insertion of other hardware combined with curettage (p < 0.001) or alone (p = 0.014). Patients who underwent ESIN insertion with curettage had a 53% healing rate, higher than insertion of other hardware combined with curettage (p = 0.009). The overall rate of postoperative complications was 25% and did not differ between groups (p = 0.228). A total of 32 limb length discrepancies were identified. Conclusion. ESIN insertion, either alone or combined with percutaneous injection or curettage and grafting, may offer higher healing rates than other operative procedures. Limb length discrepancy remains a major concern, and might be partly explained by the cyst’s location and the consequence of surgery. Therefore, providing information about this risk is crucial. Cite this article: Bone Joint J 2024;106-B(5):508–514

Aims. Temporary hemiepiphysiodesis (HED) is applied to children and adolescents to correct angular deformities (ADs) in long bones through guided growth. Traditional Blount staples or two-hole plates are mainly used for this indication. Despite precise surgical techniques and attentive postoperative follow-up, implant-associated complications are frequently described. To address these pitfalls, a flexible staple was developed to combine the advantages of the established implants. This study provides the first results of guided growth using the new implant and compares these with the established two-hole plates and Blount staples. Methods. Between January 2013 and December 2016, 138 patients (22 children, 116 adolescents) with genu valgum or genu varum were treated with 285 flexible staples. The minimum follow-up was 24 months. These results were compared with 98 patients treated with 205 two-hole plates and 92 patients treated with 535 Blount staples. In long-standing anteroposterior radiographs, mechanical axis deviations (MADs) were measured before and during treatment to analyze treatment efficiency. The evaluation of the new flexible staple was performed according to the idea, development, evaluation, assessment, long-term (IDEAL) study framework (Stage 2a). Results. Overall, 79% (109/138) of patients treated with flexible staples achieved sufficient deformity correction. The median treatment duration was 16 months (interquartile range (IQR) 8 to 21). The flexible staples achieved a median MAD correction of 1.2 mm/month/HED site (IQR 0.6 to 2.0) in valgus deformities and 0.6 mm/month/HED site (IQR 0.2 to 1.5) in varus deformities. Wound infections occurred in 1%, haematomas and joint effusions in 4%, and implant-associated complications in 1% of patients treated with flexible staples. Valgus AD were corrected faster using flexible staples than two-hole plates and Blount staples. Furthermore, the median MAD after treatment was lower in varus and valgus AD, fewer implant-associated complications were detected, and reduced implantation times were recorded using flexible staples. Conclusion. The flexible staple seems to be a viable option for guided growth, showing comparable or possibly better results regarding correction speed and reducing implant-associated complications. Further comparative studies are required to substantiate these findings. Cite this article: Bone Joint J 2023;105-B(3):331–340

Aims. There is no consensus regarding optimum timing and frequency of ultrasound (US) for monitoring response to Pavlik harness (PH) treatment in developmental dysplasia of the hip (DDH). The purpose of our study was to determine if a limited-frequency hip US assessment had an adverse effect on treatment outcomes compared to traditional comprehensive US monitoring. Methods. This study was a single-centre noninferiority randomized controlled trial. Infants aged under six months whose hips were reduced and centred in the harness at initiation of treatment (stable dysplastic or subluxable), or initially decentred (subluxated or dislocated) but reduced and centred within four weeks of PH treatment, were randomized to our current standard US monitoring protocol (every clinic visit) or to a limited-frequency US protocol (US only at end of treatment). Groups were compared based on α angle and femoral head coverage at the end of PH treatment, acetabular indices, and International Hip Dysplasia Institute (IHDI) grade on one-year follow-up radiographs. Results. Overall, 100 patients were included; 42 patients completed the standard protocol (SP) and 40 completed the limited protocol (LP). There was no significant difference in mean right α angle at the end of treatment (SP 70.0° (SD 3.2°) ; LP 68.7° (SD 2.9°); p = 0.033), nor on the left (SP 69.0° (SD 3.5°); LP 68.1° (SD 3.3°); p = 0.128). There was no significant difference in mean right acetabular index at follow-up (SP 23.1° (SD 4.3°); LP 22.0° (SD 4.1°); p = 0.129), nor on the left (SP 23.3° (SD 4.2°); LP 22.8° (SD 3.9°); p = 0.284). All hips had femoral head coverage of > 50% at end of treatment, and all were IHDI grade 1 at follow-up. In addition, the LP group underwent a 60% reduction in US use once stable. Conclusion. Our study supports reducing the frequency of US assessment during PH treatment of DDH once a hip is reduced and centred. Cite this article: Bone Joint J 2022;104-B(9):1081–1088

Aims. The aim of this study was to compare outcomes of guided growth and varus osteotomy in treating Kalamchi type II avascular necrosis (AVN) after open reduction and Pemberton acetabuloplasty for developmental dysplasia of the hip (DDH). Methods. This retrospective study reviewed patients undergoing guided growth or varus osteotomy for Kalamchi type II AVN between September 2009 and January 2019. All children who had undergone open reduction and Pemberton acetabuloplasty for DDH with a minimum two-year follow-up were enrolled in the study. Demographic and radiological data, which included the head-shaft angle (HSA), neck-shaft angle (NSA), articulotrochanteric distance (ATD), Sharp angle (SA), and lateral centre-edge angle (LCEA) at baseline, two years, and at the extended follow-up, were compared. Revision rates were evaluated. Clinical outcomes using the Harris Hip Score were assessed two years postoperatively. Results. A total of 24 patients underwent guided growth and 19 underwent varus osteotomy, over a mean period of 3.3 years (95% confidence interval (CI) 2.8 to 3.8) and 5.2 years (95% CI 4.5 to 6.0), respectively. There were no differences in demographic and preoperative radiological data, except for a younger age at time of acetabuloplasty and larger ATD for the osteotomy group. The HSA did not differ at two years and the extended follow-up because of postoperative rebound in the osteotomy group. The NSA of the osteotomy group remained smaller postoperatively. There were no significant differences in the follow-up ATD, SA, and LCEA, except for a smaller two-year ATD of the osteotomy group. Seven patients (29.2%) in the guided growth group underwent revision surgery and none in the osteotomy group. The Harris Hip Score was similar between groups. Conclusion. Guided growth and varus osteotomy had comparable results in improving caput valgum deformity, given the rebound of lateral tilting of the physis after osteotomy correction. There were no differences in clinical outcomes at two years postoperatively. Cite this article: Bone Joint J 2022;104-B(7):902–908

Aims. The aim of this study was to assess the prognostic value of the modified three-group Stulberg classification, which is based on the sphericity of the femoral head, in patients with Perthes’ disease. Methods. A total of 88 patients were followed from the time of diagnosis until a mean follow-up of 21 years. Anteroposterior pelvic and frog-leg lateral radiographs were obtained at diagnosis and at follow-up of one, five, and 21 years. At the five- and 21-year follow-up, the femoral heads were classified using a modified three-group Stulberg classification (round, ovoid, or flat femoral head). Further radiological endpoints at long-term follow-up were osteoarthritis (OA) of the hip and the requirement for total hip arthroplasty (THA). Results. There were 71 males (81%) and 17 females. A total of 13 patients had bilateral Perthes’ disease; thus 101 hips were analyzed. At five-year follow-up, 37 hips were round, 38 ovoid, and 26 flat. At that time, 66 hips (65%) were healed and 91 (90%) were skeletally immature. At long-term follow-up, when the mean age of the patients was 28 years (24 to 34), 20 hips had an unsatisfactory outcome (seven had OA and 13 had required THA). There was a strongly significant association between the modified Stulberg classification applied atfive-year follow-up and an unsatisfactory outcome at long-term follow-up (p < 0.001). Between the five- and 21-year follow-up, 67 hips (76%) stayed in their respective modified Stulberg group, indicating a strongly significant association between the Stulberg classifications at these follow-ups (p < 0.001). Conclusion. The modified Stulberg classification is a strong predictor of long-term radiological outcome in patients with Perthes’ disease. It can be applied at the healing stage, which is usually reached five years after the diagnosis is made and before skeletal maturity. Cite this article: Bone Joint J 2021;103-B(12):1815–1820