Flexible intramedullary nailing for the treatment of unicameral bone cysts in long bones

Surgical outcomes of proximal femoral bone cysts in pediatric patients: a retrospective study of 41 cases

Purpose

The aim of this study was to evaluate the surgical outcomes of proximal femoral bone cysts in pediatric patients.

Methods

We retrospectively analyzed 41 pediatric patients (31 males and 10 females, mean age 7.47 ± 2.67 years, range 2.03-14.67 years) diagnosed with proximal femoral bone cysts treated at a single institute between March 2009 and November 2021. Data included demographics, preoperative details, intraoperative conditions, surgical techniques, postoperative outcomes, recurrence, and complications.

Results

Of the participants, 68% presented with simple bone cysts and 32% with aneurysmal bone cysts. Prior to surgery, 32% exhibited pathological fractures. Surgical methods included lesion curettage, defect filling using allograft bone and Minimally-Invasive Injectable Graft ×3, and varied fixation techniques. Postoperative recurrence (17%) was associated with cyst location between the capital femoral epiphysis and the linea intertrochanterica (P = 0.010). At the final assessment (mean follow-up: 26.51 ± 18.99 months), all showed radiological bony union with 93% rated as "good" and 7% as 'fair' based on Ratliff hip scores. Complications arose in 20% of patients, significantly correlated with prior pathological fractures (P = 0.007) and their association with the linea intertrochanterica (P = 0.004). Those with fractures reported higher intraoperative blood loss (P = 0.015) and longer surgery durations (P = 0.012) compared to those without.

Conclusion

Treating pediatric proximal femoral bone cysts using techniques such as lesion curettage, defect filling, and selective internal fixation yields favorable outcomes. The presence of pathological fractures can prolong surgical time, increase intraoperative blood loss, and elevate postoperative complication risks. Hence, early surgical intervention for these cysts is recommended to prevent fractures.

Outcomes and complications of surgical treatment modalities for simple bone cysts of the humerus in children and adolescents

PURPOSE

The aim of this study was to evaluate and compare different surgical treatment modalities for simple bone cysts (SBC) of the humerus regarding their effectiveness and recurrence rate.

METHODS

In this retrospective study, patients who received surgical treatment for previously untreated primary SBCs of the humerus were analyzed. Demographic data, cyst-specific as well as treatment-specific parameters, complications, treatment failures, and recurrence rates were collected and correlated with different treatment modalities. Observed procedures were categorized as open procedure (n=20) or osteosynthesis alone (n=3). For the open procedure group, four subgroups could be defined.

RESULTS

Twenty-three patients were included. The mean age at diagnosis was 11.6 ± 2.5 years, and the mean postoperative follow-up was 3.9 ± 2.6 years (range 1.0-10.3). After surgical intervention, a total of five (21.7%) patients showed at least one recurrence. Fracture occurred in three (13.0%) cases. The incidence of treatment failure was significantly higher in the curettage, allograft, adjuvants group, with five (83.3%) of six cases showing recurrence, than in the other subgroups (≤ 25.0%) including the osteosynthesis alone group (p=.024). For the open procedure group, the failure-free survival rates were 80.0% after two years and 50.4% after five years. For the three cases treated by osteosynthesis alone, no failures were observed.

CONCLUSION

Open procedures showed similar failure rates except for the subgroup using curettage, allograft, and adjuvants which showed significantly higher treatment failure. Promising results were observed in the group which received solely osteosynthesis without cyst excision or filling, as no treatment failure was observed here.

Factors which can influence elastic stable intramedullary nailing removal in healed bone cysts in children

Elastic stable intramedullary nailing (ESIN) internal fixation is used clinically to treat pathological fractures of bone cysts in children. However, one of the most important complications was removal difficulty. In this study, we aim to analyse the factors which can influence ESIN removal in healed bone cysts in children. From April 2014 to November 2020, the clinical data of 49 children who underwent elastic stable intramedullary nail removal for pathological fractures of the bone cysts in our hospital were retrospectively analysed. The following data, including age, sex, pathological fracture site, with bone graft, number of ESINs, ESIN indwelling time, and extraosseous length of ESIN were collected, and univariate analysis and logistic regression analysis was performed. The frequency of difficulty in ESIN extraction was 44.90% (22/49). The univariate logistic regression analysis showed that age,ESIN indwelling time,with bone garft and extraosseous length of ESIN may be correlated with the difficulty in removing ESIN (P < 0.05), while sex, pathological fracture site, number of ESIN may not be correlated with the difficulty in removing ESIN (P > 0.05).The multivariate logistic regression analysis showed that the ESIN indwelling time was the independent influencing factor for difficulty in removing ESIN (P < 0.05). The factors influencing the ESIN removal in healed bone cysts in children include over 11.79 years old, the long indwelling time of the ESIN(over 10.5 months),with bone graft and short extraosseous length of ESIN(≤ 0.405 cm). These factors influencing ESIN removal in healed bone cysts in children should be considered.

Surgical management of proximal femoral unicameral bone cyst in children

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.

Pathological fracture increases the risk of unsatisfactory functional results and avascular necrosis in children with proximal femur simple bone cysts

INTRODUCTION

Proximal femur simple bone cysts (SBCs) are rare in children, but with a risk of pathological fractures and the associated poor outcomes. This study aimed to evaluate the functional and radiographic outcomes of children with proximal femur SBCs.

PATIENTS AND METHODS

38 children with proximal femur SBCs treated surgically at our department, West China hospital, were enrolled in the study. Patients were divided into two groups according to whether pathological fractures presented before treatment. The non-fracture group received treatment of open curettage, cavity electrocauterization, bone grafting, and fixation (proximal femoral plate, intramedullary nail or Kirschner wire). The pathological fracture group received the same procedures of curettage, electrocauterization, grafting, and fixation. Autogenous iliac bone grafting was done in all cases, and the artificial bone was used as a supplementary based on the size of the cavity. Postoperatively, all patients underwent hip spica or similar orthosis immobilization for six weeks and received the same rehabilitation program after the removal of hip spica. Patients were evaluated by two independent observers, including the functional results based on the Ratliff's criteria, avascular necrosis, healing rate based on the Neer scoring system, coxa vara, and premature physeal arrest. We described the good outcome in Ratliff's criteria as "Satisfactory results", and fair and poor outcomes as "Unsatisfactory results." Grade 1 and grade 2 Neer results were termed as failures in treatment, and grades 3 and 4 were considered successes and healing.

RESULTS

38 patients with 38 hips (18 on the left side and 20 on the right side) were evaluated, including 9 females and 29 males, with a mean age of 9.0±2.6 years old (range, 5 to 14 years). There was no significant difference between these two groups in the baseline data of gender, age, side, grafting, staging, and fixation methods. The rate of unsatisfactory functional results in the pathological fractures group was 56.3% (9/16), significantly higher than that in patients without fracture (22.7%, 5/22. p= 0.047). There was also a significant difference in avascular necrosis of the femoral head between the pathological fractures group (7/16) and the group without fracture (2/22, p=0.021). Thirty cases presented with healing, including 13 in the fractures group and 17 in the non-fracture group (p=1.000), and eight cases were graded as failures (2 cases of grade 1 and 6 cases of grade 2). There were also no significant differences between these two groups in premature physeal arrest (2 in fracture group and 1 in non-fracture group, P=0.562), and Coxa vara (3 in the fracture group and 0 in non-fracture group, P=0.066).

CONCLUSIONS

Pathological fracture significantly increases the risk of unsatisfactory functional results and avascular necrosis of the femoral head in patients with femoral neck SBCs. Prophylactic treatment and fixation of SBCs in weight bearing proximal femur region is better to manage without complications than managing with pathological fractures.

Results of Allografts and Synthetic Grafts in Humeral Simple Bone Cysts

PURPOSE OF THE STUDY

Simple bone cysts (SBCs) are the most common benign bone lesions in childhood. There are many different methods in the treatment of SBCs. There is no consensus on which method to use in the treatment. In this study, we compared the results of allogeneic bone graft or synthetic bone graft in addition to fl exible intramedullary nail (FIN) for SBC located in the humerus.

MATERIAL AND METHODS

This retrospective study comparing the data of 19 (group 1: 8 curettage, allograft and FIN; group 2: 11 curettage, synthetic graft and FIN) patients with a mean age of 11.4 (6 to 26; seven female, twelve male) who were surgically treated in our hospital for humeral SBC between April 2014 and January 2020. Patient data included age, sex, anatomical side, stage of the cyst, pathological fracture, previous treatments and complications.

RESULTS

The mean follow-up period was 33.7 months (12 to 61). The average last follow-up Musculoskeletal Tumor Society functional scores for groups 1 and 2 were 27.8 (20 to 30) and 28.6 (21 to 30) (P > 0.05). Complete or signifi cant partial radiographic healing rates were achieved in group 1 (75%) compared with group 2 (81.9%). The reoperation rates for groups 1 and 2 were 62.5% (5/8; three for nails removed, two for recurrence) and 36.3% (4/11; two for nails removed, two for recurrence). One patient in group 2 had a 15° varus deformity due to recurrence. No other complications were observed.

CONCLUSIONS

The combination of curettage-grafonage FIN is a common treatment method in recent years, as it provides early cyst healing and limb mobilization in SBCs located in the upper extremity. For defects after curettage of the bone cysts, allogeneic or synthetic grafts (granule b-tricalcium phospate) which have similar results in terms of healing can be used as an alternative to each other.

KEY WORDS

allografts, bone cysts, bone nails, synthetic grafts, humerus.

Treatment and Outcomes of 4,973 Unicameral Bone Cysts: A Systematic Review and Meta-Analysis

» Unicameral bone cysts (UBCs) can increase the risk of pathologic fractures of both long and short bones. Although multiple treatments exist, data are conflicting regarding optimal management.

» We sought to analyze treatment strategies for UBCs and their rates of successful treatment.

» Success rates were analyzed according to treatment modality, with emphasis on filling techniques and/or decompression associated with curettage, and injection compounds.

» Curettage with bone substitute and cyst decompression was identified as a highly successful technique for UBC treatment.

» Decompressing the cyst wall after injection, regardless of the specific compound used, had a greater potential to enhance healing rates.

» The management decision should be individually guided within the patient's context.

Outcomes in Unicameral Bone Cyst Management Utilizing a Decision Tree Algorithm Approach

OBJECTIVE

To determine if utilization of a decision tree algorithm could improve the healing rate of unicameral bone cysts (UBCs).

METHODS

Creation of the decision tree algorithm was based on previous literature and assessment of our clinical practice. Demographic, treatment, and radiographic data were collected retrospectively. Radiographic healing was determined using the Neer classification. Healing rate, as well as clinical/radiographic characteristics, were compared based on adherence to the treatment algorithm.

RESULTS

Forty-seven subjects were included. Mean age at initial surgery was 10.0 ± 3.3 years in children following the algorithm and 9.1 ± 3.2 years in those deviating from the algorithm (p = 0.393). Follow-up was found to be similar among those following the algorithm (37.5 ± 15.8 months) and those deviating from the algorithm (45.2 ± 24.6 months), p = 0.38. Children who followed the algorithm healed at a rate of 75%, while children who deviated from the algorithm healed at a rate 67% (p = 0.552).

CONCLUSIONS

Although we reject our hypothesis that a decision tree algorithm for the management of UBCs in the pediatric population could improve the healing rate, we believe that we uncovered some utility in applying an algorithm to this pathology. Our algorithm was designed to minimize risk to the child and maximize healing with the least number of surgical events. Treating surgeons should consider this proposed pathway to determine the best treatment and to help families understand that these lesions rarely heal with a single-event surgery.

Evaluation of different treatment modalities for fractured and non-fractured simple bone cyst: A single-center review of 68 patients

Simple bone cysts (SBCs) occur most frequently in the proximal aspect of the humerus and femur in growing age and are associated with intercurrent pathological fractures in up to 87%. Therapeutic management of SBCs remains controversial. The aim of this study was to examine the outcome of conservative and various surgical treatment modalities considering the specific anatomic location and integrity of the SBC.In this retrospective study, we analyzed 68 cases of SBCs who underwent a conservative or surgical treatment between 2009 and 2020 with a mean follow-up of 30.1 months. The epidemiological characteristics, complications, clinical, and radiographic outcome after conservative or surgical treatment were assessed.The study includes 50 male (73.5%) and 18 female (26.5%) patients with a mean age of 9.1 years. The most common locations were the proximal humerus (69.2%, n = 47) and femur (16.2%, n = 11). In 43 cases (63.2%; upper limb n = 40, lower limb n = 3) a pathological fracture occurred. Fifty patients (73.5%; upper limb n = 40, lower limb n = 10) underwent a conservative treatment. In 11 cases (16.2.1%; upper limb n = 4, lower limb n = 7) an intralesional curettage and defect reconstruction with bone substitute without stabilization were performed. Five patients (7.3%; upper limb n = 4, lower limb n = 1) received an osteosynthesis, in two cases (2.9%; upper limb 1; lower limb 1) combined with an intralesional curettage and defect reconstruction with bone substitute. All 32 pathological fractures treated conservatively (upper limb n = 31, lower limb n = 1) healed within 6 weeks; 17/43 patients (39.5%) suffered at least one second fracture. After intralesional curettage and defect reconstruction with bone substitute local recurrence was observed in 5/13 cases (38.5%). Spontaneous consolidation, at least partially, was observed in three cases (4.4%) following conservative treatment after fracture. No relevant secondary angular or torsional deformity was observed after treatment.The majority of SBCs can be treated conservatively, especially in the upper extremity. However, if a fracture is completely dislocated, joint affecting, unstable or open, surgical treatment is necessary. Load-dependent pain or the inability to mobilize timely after fracture can necessitate surgical treatment in SBCs affecting the lower extremity. Spontaneous resolution, especially after fracture, can be seen in rare cases.

Distraction osteogenesis at the site of previously cystic bone lesion of femur: A case report

Introduction and importance

Limb length discrepancy can be occurred as residual problems after bone cyst treatment. Distraction osteogenesis is one of surgical option to treat this problem.

Case presentation

A male 27 years old came with 3 cm residual lower limb discrepancy after treatment of femoral aneurismal bone cyst (ABC). Distraction osteogenesis has been successfully performed to treat this case at the site of previously cystic bone lesion.

Conclusion

Good quality of callus could be expected at the site of distraction osteogenesis that previously a cystic bone lesion.

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Lower limb length discrepancy (LLD) occurred after aneurismal bone cyst (ABC) of femur treatment

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Distraction osteogenesis has been performed to this case

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The distraction procedure has been performed “at the site” of cystic lesion

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Callus formation was good and resulted excellent functional outcome

Does the management of osteofibrous dysplasia of the tibia and fibula in children should be tailored to the extent and location of the lesion? A case control study investigating different surgical options

BACKGROUND

Osteofibrous dysplasia (OFD) is a rare non neoplastic, self-limited intracortical fibro-osseous lesion that most commonly affects the diaphysis of the tibia and fibula of children, the best treatment is still debated. Therefore we performed a retrospective study in children mostly under 10 years old with OFD aiming to determine whether early surgery is necessary and which is the best treatment.

HYPOTHESIS

Symptomatic OFD lesions should be treated proactively, and appropriate treatment can achieve favorable outcome.

METHODS

We retrospectively reviewed 23 patients with OFD of the tibia (n=22) and fibula. Management varied according to the severity of symptoms (deformity, pain or pathological fracture) and the extent of the lesion. Cases were divided into four groups (Gr.): Gr. 1: observation (n=4); Gr. 2: curettage and allograft (n=6); Gr. 3: curettage, allograft and elastic stable intramedullary nailing (ESIN) fixation (n=9); Gr. 4: extra-periosteal resection and bone transport (n=5). One patient received two different treatments successively (23 patients and 24 cases). All patients had regular clinical and radiographic follow-up to assess bone consolidation and complications.

RESULTS

In Gr. 1, four asymptomatic patients underwent observation after open biopsy. Gr. 4 had the lowest local recurrence rate: 0 cases (0%) vs. 4 (66.7%; Gr. 2) vs. 1 (11.1%; Gr. 3) (p=0.002), incidence of deformity: 0 case (0%) vs. 0 (0%; Gr. 2) vs. 3 (50%; Gr. 3) (p=0.023), and pathological fracture: 0 case (0%) vs. 0 (0%; Gr. 2) vs. 1 (16.7%; Gr. 3) (p=0.006), although the consolidation time was longer: 6.8 vs. 2 (Gr. 2) vs. 2.7 months (Gr. 3) (p=0.017) and the rate of complication was higher than those of Gr. 2 and Gr. 3 (p<0.05). Gr. 3 had a lower local recurrence rate: 1 case (11.1%) vs. 4 cases (66.7%) (p=0.002), incidence of deformity: 0 case (0%) vs. 3 cases (50%) (p=0.023), and pathological fracture: 0 case vs. 1 case (16.7%) (p=0.006) than Gr. 2.

DISCUSSION

Open biopsy is an important step in the management of patients with imaging suggestive of OFD in order to rule out Adamantinoma and other bone tumors or infection. Observation should be reserved for asymptomatic patients, while surgical treatment is indicated in patients with persistent pain, pathological fracture or significant deformity of the tibia. ESIN is a valid option to preserve the anatomical axis of the tibia in symptomatic patients with lesions of limited size; large circumferential lesions or recurrence can be managed by extra-periosteal resection and bone transport, although the complication rate can be relatively high.

LEVEL OF EVIDENCE

III; case control study.

Comparison of three treatment methods for simple bone cyst in children

BACKGROUND

The unicameral bone cyst (UBC) is a kind of benign tumor whose clinical treatments and efficacy are controversial. The purpose of this study was to evaluate the efficacy of the elastic stable intramedullary nail (ESIN), the injection of autologous bone marrow (ABM), and the combination of ESIN and ABM in the treatment of bone cyst in children.

METHODS

Eighty-three cases with simple bone cyst were analyzed retrospectively. Twenty-eight cases were treated with ABM. Twenty-eight cases were treated with ESIN. Twenty-seven cases were treated with ABM and ESIN. All cases were diagnosed through X-ray, CT, or MRI scans. For the suspicious ones, the pathological biopsy was performed for an accurate diagnosis. X-ray examinations were carried out for the postoperative follow-up. Capanna criteria for bone cyst was used for postoperative evaluation of three methods.

RESULTS

All cases accomplished the follow-up. The effective rate of the ABM + ESIN group was significantly higher than that of the ABM group (P < 0.05), and the cure rates of the ESIN group and the ABM + ESIN group were higher than that of the ABM group (P < 0.05, respectively). The cure time in the ESIN group was lower than that of the other two groups (P < 0.05, respectively). The times for admission were 2.0 ± 0.0 in the ESIN group, 5.7 ± 1.9 in the ABM group, and 4.7 ± 2.4 in the ABM + ESIN group (P < 0.05 when compared with each other).

CONCLUSIONS

The method of ABM combined with ESIN for children's bone cyst has the highest effective rate and curative rate. For the individual method, ESIN has a higher effective rate and curative rate than that of ABM. Meanwhile, it has the fewest time of hospitalization.

Is elastic stable intramedullary nail a good choice for pathological fractures of the proximal femur due to simple bone cyst in pediatric population?

Pathological fracture of the proximal femur represents a challenging situation for orthopedic surgeons because of the high risk of non-union, varus union, and avascular necrosis (AVN) of the femoral head. This study aims to investigate the efficacy of ESINs for the treatment of proximal femoral fractures caused by simple bone cysts (SBCs).All the patients with a diagnosis of proximal femoral fracture secondary to SBC treated with ESINs combined with bone grafting between January 2008 and January 2018, were analyzed retrospectively.In all, 11 patients were included in the Double ESINs group (5.1 ± 0.8 years, 5 male, 6 female) and 27 patients were included in the Triple ESINs group (9.1 ± 2.1 years, 11 male, 16 female). There was no significant difference between the 2 groups concerning the patients demographic parameters, including sex and affected side. However, the age in the Double group was significantly younger than those in the Triple group (P < .001). All patients in both groups displayed excellent outcomes according to the Musculoskeletal Tumor Society Score (MSTS), and there was no significant difference between the 2 groups at a 12-month follow-up evaluation (P = .10). As for the Capanna classification (1 + 2), there was no significant difference between these 2 groups (P = .24). In the Triple ESINs group, 24 (88.9%) patients were categorized in Capanna 1 and 2, whereas all patients in Double ESINs were Capanna 1 and 2. Overall, the success rate was 92%.ESINs combined with bone grafting is a successful strategy for proximal femoral fractures caused by SBCs in the pediatric population.

Evaluation of immediate and delayed surgery for pathological fracture due to unicameral bone cysts in children

PURPOSE

Unicameral bone cysts (UBCs) are most often found when accompanied by a pathological fracture. In these cases, the doctor must determine the optimal timing for the surgery. The purpose of this study was to evaluate the outcome of immediate surgery as compared with delayed surgery in paediatric pathological fractures due to UBCs.

METHODS

This retrospective study assessed the medical records of 65 patients between January 2012 and September 2016. Group A included 34 patients who underwent immediate surgery, including curettage, demineralized bone matrix and fixation with elastic stable intramedullary nailing. Group B included 31 patients who underwent the same surgery several months later. The outcome evaluations included the radiological changes, brace fixation time, cyst healing time, at the first-, third- and sixth month, and final visit.

RESULTS

The mean brace fixation time was 26.3 days (sd 5.7) for group A and 53.8 days (sd .1) for group B (p = 0.012). According to radiological evaluations, 3/34 patients in group A and 5/31 in group B had recurrence after the first surgery. A second surgery was performed in all cases of recurrence, and all fractures were healed at the last visit. There was no significant difference in the recurrence rate between the two groups (p = 0.4631), and healing times were also similar (p = 0.6033).

CONCLUSION

Both the immediate and delayed surgery were safe for the treatment of UBCs with fractures. We suggest immediate surgery for shorter fixation time and early activity.

LEVEL OF EVIDENCE

IV.

Injectable calcium sulfate vs mixed bone graft of autologous iliac bone and allogeneic bone: Which is the better bone graft material for unicameral bone cyst in humerus?

Unicameral bone cyst (UBC) is a benign fluid-filled lesion, mainly located in the metaphyses of long bones in children and adolescents. Elastic stable intramedullary nail (ESIN) is adopted in our institute for UBCs since 2010, and bone grafting was performed simultaneously. This study aims to evaluate the efficacy of ESIN decompression combined with different bone graft materials.All patients with the diagnoses of UBCs of the humerus, treated with ESINs and bone grafting between January 2010 and June 2018, were analyzed retrospectively. The bone grafting included injectable calcium sulfate, a mixture of the autologous iliac bone and allogeneic bone. All patients were categorized into 2 groups: ICS (injectable calcium sulfate) group and MIX (a mixture of the autologous iliac bone and allogeneic bone, ratio: 1:3) group. All the information was collected from the Hospital Database.In all, 17 patients (8.8 ± 2.3-year-old, male 8, female 9) in the ICS group and 19 patients (8.9 ± 1.9-year-old, male 10, female 9) in the MIX group were included in this study. Patients in both groups were followed up for more than 2 years (average, 3.4 ± 1.3 years). No recurrence was observed in either group. There was no significant difference between the two groups concerning the patient's demographic parameters, including sex, age, and affected side. All patients in both groups displayed excellent and good shoulder function, and there was no significant difference between the 2 groups (P = .29). As for the Capanna classification, there was no significant difference between these 2 groups (P = .78).Intramedullary nailing has the advantage of a minimally invasive procedure, immediate stability, and continuous decompression. ICS showed similar results as a mixture of the autologous iliac bone and allogeneic bone.

Treatment of simple bone cysts of the humerus by intramedullary nailing and steroid injection

Background

Simple bone cysts (SBCs) are common benign lytic bone lesions in children. This study focused on exploring a clinical treatment method, minimally invasive intramedullary decompression and drainage with elastic stable intramedullary nailing (ESIN) combined with intralesional injections of steroids, and evaluated its effectiveness, complications and morbidity through functional and radiographic outcomes.

Methods

The postoperative recovery of 18 children who suffered from SBCs of humerus was evaluated (mean follow-up, 40 months) from January 2009 to December 2016. These patients (11 males, 7 females; 8 in the left, 10 in the right; mean age, 10.9 years old) were treated with minimally invasive intramedullary decompression and drainage with ESIN combined with intralesional injections of steroids. The diagnosis was based on not only pre-operative typical medical images (X-rays/CT/MRI) but also surgical findings and pathological diagnosis. Radiological and functional outcomes were evaluated according to Capanna and Musculoskeletal Tumor Society (MSTS) score. The interclass differences were analyzed by t-test.

Results

According to Capanna and MSTS criteria, after treatment, 14 patients made full recoveries which was presented by all the cysts filled with bone tissue, and 4 patients made partially recoveries, which were presented by cystic spaces partially filled with low density bone. All the cysts responded to treatment method, and there was no cyst recurrence. All except 2 patients had good functional results. One of the two patients had irritation of the end of the nail and one patient had a valgus deformity.

Conclusions

Treatment for SBCs of humerus by minimally invasive intramedullary decompression and drainage with ESIN combined with intralesional injections of steroids is safe, effective and convenient. The clinical effect is satisfactory and worth popularizing.

Percutaneous cyst aspiration with injection of two different bioresorbable bone cements in treatment of simple bone cyst

INTRODUCTION

Simple bone cysts (SBCs) are common in children and adolescents. The risk of refracture and the probability of spontaneous healing in SBCs are mainly dependent on the activity of the cyst and can be quantified with the Cyst-Index. Avoiding pathological fractures is the primary goal. Our study presents a comparison of two different bioresorbable bone graft substitutes (BGSs) in the minimally-invasive treatment of SBC in the active stage by percutaneous cyst aspiration and injection.

METHODS

Between 2006 and 2017, 38 patients (aged two to 37 years; mean age 12.4 (sd 5.6)) were treated with percutaneous cyst aspiration and refilled with bioresorbable BGSs in three hospitals. The cysts of 21 patients (11 humerus, five femur, four calcaneus, one fibula) were refilled with porous beta-tricalcium phosphate (PB-TP group) (ChronOS Inject) and of 17 patients (nine humerus, six femur, one calcaneus, one fibula) with hydroxyapatite/calcium sulphate (H/CS group) (CERAMENT|BONE VOID FILLER). There were 13 (62%) preceding fractures in the PB-TP group and eight (47%) in the H/CS group. The follow-up of all patients was at least two years. During follow-up, radiological healing (modified Neer classification), activity level, refracture rates, recurrence rates, resorption period and complications were analyzed.

RESULTS

In all, 21 patients treated with PB-TP group experienced 27 operations (one refracture, three recurrences and one persistent cyst). A total of 17 patients treated with H/CS experienced 20 operations (one refracture and one recurrence). After six weeks, 95% in the PB-TP group returned to unrestricted activity with one refracture in the femur due to insufficient biomechanical stability and all returned to unrestricted activity in the H/CS group. Partial or complete radiological response was observed in 81% after 13 months (sd 3.4). Three recurrences (14%) occurred in the PB-TP group and one recurrence (6%) occurred in the H/CS group. The refracture rates were similar in both groups; one (5%) in the PB-TP group and one (6%) in the H/CS group. All H/CS treated cysts showed completed resorption after two years, whilst in PB-TP treated cysts no resorption occurred in five cases (25%) (p = 0.031). Two (10%) wound infections occurred in the PB-TP group and no infections occurred in the H/CS group.

CONCLUSION

Both PB-TP and H/CS can provide stability and prevent refracture in patients with single bone cysts at the upper extremity or the foot. For the proximal femur, additional stabilization is necessary, due to the weight-bearing and associated high refracture rate. The H/CS bone graft substitute has a better resorption rate than the PB-TP graft.

LEVEL OF EVIDENCE

III.

Current Trends and Variations in the Treatment of Unicameral Bone Cysts of the Humerus: A Survey of EPOS and POSNA Members

BACKGROUND

A variety of treatment methods have so far been described for unicameral bone cysts (UBC). However, to the best of our knowledge, no particular consensus has yet been reached on when to operatively treat a patient with a humeral UBC. Therefore, members of the European Pediatric Orthopedic Society (EPOS) and Pediatric Orthopedic Society of North America (POSNA) were surveyed to characterize current treatment preferences.

METHODS

An online electronic questionnaire was sent out to all registered EPOS and POSNA members. The survey comprised 45 questions related to the diagnosis, treatment, and follow-up characteristics of patients with UBCs of the humerus. Particular questions related to the nonoperative or surgical treatment of pathologic proximal humerus and humeral shaft fractures were also included.

RESULTS

In total, 444 participants (132 EPOS and 292 POSNA members) responded, of whom 400 were actively involved in UBC treatment. The preferred diagnostic modalities to confirm the diagnosis of a UBC in the humerus were radiographs (88%), MRI in cases of questionable diagnosis (58%) or CT scan (8%). For painless UBCs 67% prefer no treatment at all except when the fracture risk is deemed high (then 53% recommend surgery); 71% of respondents would treat painful UBCs with surgery. Most common surgical techniques comprise curettage (45%), artificial bone substitutes (37%), corticosteroid injection (29%), or intramedullary stabilization (eg, rodding; 24%).Fractured, nondisplaced and mildly displaced proximal humerus UBCs and mildly displaced pathologic humerus shaft fractures are all preferably treated nonoperatively (94%, 91%, 83%, respectively). Severely displaced pathologic proximal humerus fractures are treated less often conservatively (36%) than surgically (40%), and severely displaced humerus shaft fractures are preferably treated surgically (63%) by intramedullary stabilization (60%).

CONCLUSIONS

There is great variation among EPOS and POSNA members with regards to the diagnosis and treatment of UBCs in the humerus. Although some consensus on general treatment principles is seen, specific surgical treatment indications vary.Prospective randomized-controlled studies are needed to evaluate the outcomes of the different surgical approaches compared with nonoperative strategies.

LEVEL OF EVIDENCE

Level V-expert opinion.

Treatment of simple bone cyst with bone marrow concentrate and equine-derived demineralized bone matrix injection versus methylprednisolone acetate injections: A retrospective comparative study

OBJECTIVE

The aim of this study was to compare the outcome of intra-lesional autologous bone marrow concentrate (BMC) and equine derived demineralized bone matrix (EDDBM) injections with methylprednisolone acetate injections in patients with simple bone cyst.

METHODS

Clinical records and radiographs of 53 consecutive patients (37 females,and 16 males; mean age: 10.6±1.53 years) treated between 2006 and 2016 were retrospectively reviewed. Healing was assessed by an independent radiologist according to Neer scoring system. Functional outcome was assessed with the Activity Scale for Kids (ASK). Thirty-four cysts were in the humerus, 13 in the femur and 6 in other locations. Twenty-nine patients were included in Steroid Group and treated with 3 cycles of injections of methylprednisolone acetate, while 24 patients were treated with injection of autologous bone marrow concentrate and equine derived demineralized bone matrix (BMC+ EDDBM Group). The two groups were homogenous for the mean age, sex distribution, cysts location and their clinical presentation.

RESULTS

At a minimum follow-up of 24 months, success rate (Neer/Cole score 3 and 4) was higher in EDDBM+BMC group (83.3% vs 58.6%; p=0.047). Female patients had higher healing rates in both groups (p=0.002). No association was found between healing and age (p=0.839), cyst activity (p=0.599), cyst localization (p=0.099) and clinical presentation (p=0.207). BMC+EDDBM group showed higher ASK score (p=0.0007).

CONCLUSION

Treatment with BMC+EDDBM injections may provide better results with a single procedure than 3 methylprednisolone acetate injections and represent an interesting alternative for the treatment of unicameral bone cysts.

LEVEL OF EVIDENCE

Level III, Therapeutic Study.

Calcium Sulfate/Calcium Phosphate Bone Void Filler in the Treatment of Bilateral Adolescent Unicameral Calcaneal Bone Cysts: 36-Month Follow-Up

A 36-month follow-up of the management of bilateral adolescent unicameral bone cysts in a high school gymnast treated with a calcium sulfate/calcium phosphate (CSCP) bone void filler (BVF) is presented. The more developed left calcaneal cyst was managed with a traditional, open approach consisting of allogenic bone graft, CSCP BVF mixed with platelet-rich plasma. The less developed right calcaneal cyst was managed with a less used approach, a percutaneous bone cortex incision with only the CSCP BVF. The rationale for the selection between the open and percutaneous approaches, long-term BVF incorporation, and positive patient outcome allowing a quick return to athletics are presented.

Comparison of curettage and bone grafting combined with elastic intramedullary nailing vs curettage and bone grafting in the treatment of long bone cysts in children

To compare the efficacy of curettage and bone grafting combined with elastic intramedullary nailing (EIN) vs curettage and bone grafting in the treatment of long bone cysts in children and to clarify the necessity of using EIN in the treatment of bone cysts.Sixty-two patients were involved in this study from Jan. 2009 to Sept. 2017 (43 males, 19 females; 27 humeri, 35 femurs); the patients were assigned to an EIN group, comprising 30 patients who underwent curettage and bone grafting combined with EIN, or to a non-elastic intramedullary nailing (NEIN) group, comprising 32 patients who underwent curettage and bone grafting alone. The prognosis of the 2 groups was assessed with reference to the standard of Capanna.No statistically significant differences in sex, age, location, activity, pathological fracture, cyst volume, operative time and intraoperative blood loss were found between the 2 groups (P > .05). The effective rate was 90.0% in the EIN group and 68.8% in the NEIN group, and the difference was statistically significant (P < .05).Compared to simple curettage and bone grafting, curettage and bone grafting combined with EIN treatment can significantly improve the prognosis of children with bone cysts. It is recommended that EIN be added to bone cyst curettage and bone grafting.

Comparison of three surgical treatment options for unicameral bone cysts in humerus

Treatment of unicameral bone cysts (UBC) in the humerus with drainage screws is scarcely reported in the literature. The aim of this retrospective study was to compare drainage screws and alternative treatment methods with respect to the number of required surgical procedures to achieve sufficient UBC healing, postoperative fractures/recurrences/complications, and radiological outcome. Medical archives of two tertiary orthopedic referral centers were screened for all patients who were treated surgically for humeral UBC in the period 1991-2015 with a histologically/cytologically confirmed diagnosis. Sex, age, all surgical procedures, fractures, complications, recurrences, and the final radiological outcome were compared between patients treated with drainage screws, elastic intramedullary nails, or curettage with optional grafting. The study included 106 operated patients with a mean age of 10.3 years, with a mean follow-up of 5.7 years. The average number of UBC-related surgical procedures in sex-matched and age-matched treatment groups was 2.7 with drainage screws, 2.8 with intramedullary nails, and 3.5 with curettage/grafting (P=0.54). Intramedullary nails (odds ratio 0.20) and older age (odds ratio for each year 0.83) predicted a lower risk of postoperative UBC recurrence. Patients with drainage screws had the highest UBC recurrence rates and the lowest rates of changed initial treatment method. There was no difference between the treatment groups in the postoperative fracture rate, complications, or the final radiological outcome. UBC treatment in the humerus therefore requires approximately three surgical procedures, irrespective of the treatment modality chosen. Adding an elastic intramedullary nail to a humeral UBC cyst may reduce recurrence risk and prevent further fractures. Level of Evidence: Level III - therapeutic retrospective comparative study.

Pronounced femur malunion after pathological bone fracture due to a simple bone cyst in the shaft of the femur, treated using Ilizarov fixation: a case report

Background

Although a simple bone cyst carries the risk of pathological fractures, it rarely causes severe deformity. Here we report a case of severe femoral deformity after multiple pathological fractures due to simple bone cysts, and consider the reason for the progression of malunion despite multiple previous treatments. Finally, we propose a treatment option for malunion correction.

Case presentation

A 9-year, 7-month-old Japanese girl was referred to our facility with obvious deformity of her right femur, caused by multiple simple bone cyst-related pathological fractures. The deformity included bowing of approximately 90° and an internal rotation of 60° in the middle third of the femoral shaft. To correct this deformity, we excised the lesion, thus shortening the femur, then corrected the alignment and applied an Ilizarov fixator to extend the bone. At present, 3 years after surgery, the deformity has not recurred and our patient is living without any limitations in daily activities or regular exercise.

Conclusions

When a long bone is in a prolonged state of deformation, the deformity not only progresses as the bone grows, but the soft tissues remain unbalanced and treatment becomes increasingly difficult. To prevent increasing bone deformity and fragility, the deformity should be corrected as quickly as possible using intramedullary nailing or other fixation techniques. We believe that our shortening-distraction method is effective for the treatment of severe deformity with unbalanced soft tissues.

Injection of Unicameral Bone Cysts with Bone Marrow Aspirate and Demineralized Bone Matrix Avoids Open Curettage and Bone Grafting in a Retrospective Cohort

BACKGROUND

Many treatment options exist for unicameral bone cysts (UBC), without clear evidence of superiority. Meta-analyses have been limited by small numbers of patients in specific anatomic and treatment subgroups. The purpose of this study was to report the outcomes of injecting bone marrow aspirate and demineralized bone matrix (BMA/DBM) for the treatment of proximal humerus UBC.

METHODS

Fifty-one patients with proximal humerus lesions treated by BMA/DBM injection were retrospectively reviewed from a single academic medical center.

RESULTS

The mean number of injections performed per patient was 2.14 (range 1-5). Eleven patients underwent only one injection (22%), an additional 19 patients completed treatment after two injections (37%), four patients healed after three injections (8%), and one patient healed after four injections (2%). The cumulative success rate of serial BMA/DBM injections was 22% (11/51), 58% (30/51), 67% (34/51), and 69% (35/51). Eleven patients (22%) ultimately underwent open curettage and bone grafting, and five patients (10%) were treated with injection of calcium phosphate bone substitute.

CONCLUSION

A BMA/DBM injection strategy avoided an open procedure in 78% of patients with a proximal humerus UBC. The majority of patients underwent at least 2 injection treatments.

LEVEL OF EVIDENCE

Level IV retrospective cohort study.

Outcome of Conservative Versus Surgical Treatment of Humeral Shaft Fracture in Children and Adolescents: Comparison Between Nonoperative Treatment (Desault's Bandage), External Fixation and Elastic Stable Intramedullary Nailing

BACKGROUND

The main objective of this study was to retrospectively evaluate the clinical and radiographic outcomes of displaced humeral shaft fractures in children treated by Desault's bandage (DB), external fixation (EF), and elastic stable intramedullary nailing (ESIN).

METHODS

During the study period, 36 consecutive children with displaced humeral shaft fracture were treated by DB (Group A), EF (Group B) or ESIN (Group C). All the patients underwent full-length preoperative and postoperative anteroposterior and lateral radiographs of the injured humerus. One year after the index surgery, patients were asked to answer the short version of the Disabilities of the Arm, Shoulder and Hand outcome questionnaire (Quick DASH).

RESULTS

Ten patients (27.8%) were in Group A, 11 (30%) in Group B, and 15 (41.7%) in Group C. Mean age at the time of injury was 10.8±2.3 years (range, 8 to 15.2 y), 11.7±2.5 years (range, 6.8 to 15.9 y), and 12.7±2.2 years (range, 6.9 to 15.3 y) in Groups A, B, and C, respectively (P=0.08). Groups A, B, and C did not differ significantly in their demographics (P>0.05).Surgical treatment (Groups B and C) provided a better radiologic outcome than nonoperative treatment (Group A) (P=0.05). No statistically significant differences were observed for preoperative, postoperative and at last follow-up mean displacement between Groups B and C (P>0.05).Overall, 9 of 36 patients developed a complication: 2 in Group A (20%), 4 in Group B (37%), and 3 in Group C (20.1) (P=0.92).Mean Quick DASH score was 3±8.6 (range, 0 to 27.3), 1.4±2.9 (range, 0 to 9), and 1.2±4.7 (range, 0 to 18.2) in Groups A, B, and C, respectively. All the patients were able to resume previous physical and sport activities 4 to 6 months after the last fracture reduction procedure.

CONCLUSIONS

Surgery is not contraindicated in children with displaced humeral shaft fractures. EF and ESIN provide a better radiologic outcome, less posttreatment pain and faster mobilization than DB. However, numerical differences, although statistically significant, were not clinically relevant for all variables but immobilization time. Nonoperative treatment was as efficacious as surgical treatment apart from the length of time for immobilization.

LEVEL OF EVIDENCE

Level III.

A comparative study for the treatment of simple bone cysts of the humerus: open curettage and bone grafting either without instrumentation or with intramedullary nailing

Functional and radiographic outcomes, in addition to complication and reoperation rates of open curettage and grafting without instrumentation or with intramedullary nailing, in the treatment of simple bone cysts (SBCs) of the humerus were compared. Thirty-seven children [25 males, 12 females; median age=9.5 years (range, 3-17 years)] with humeral SBC were treated with curettage and grafting without instrumentation (group 1, 21 patients) or with intramedullary nailing (group 2, 16 patients). The pathological fracture rate was 85.7% in group 1 and 87.5 in group 2. The follow-up duration ranged from 26 to 85 months. The average last follow-up Musculoskeletal Tumor Society functional scores for groups 1 and 2 were 28.9 and 29.5 (P>0.05). Higher, but statistically insignificant (P>0.05), complete or significant partial radiographic healing rates were achieved in group 2 (100%) compared with group 1 (76.2%). The overall complication rate of the entire study population was 21.6% (19%; 4/21 in group 1; 25%; 4/16 in group 2). The reoperation rates for groups 1 and 2 were 9.5% (2/21; one for partial cyst healing, one for recurrence) and 56.25% (9/16; one for surgical complication, eight for implant removal). Surgical intervention is indicated for selected patients with SBCs. Even though perfect functional results were possible with open curettage and grafting, continuous intramedullary decompression with elastic nails led to a higher radiographic healing rate in the treatment of humeral SBCs. Open curettage and grafting with or without intramedullary nailing was associated with a high number of complications, but the rate of reoperation for complications was very low.

A treatment strategy for proximal femoral benign bone lesions in children and recommended surgical procedures: retrospective analysis of 62 patients

PURPOSE

We aimed to develop a surgical treatment strategy for benign bone lesions of the proximal femur based upon retrospective review of our data in 62 children.

METHODS

Sixty-two children [38 male, 24 female; median age 9 years (range 5-18 years)] with proximal femoral benign bone lesions were surgically treated between 2005 and 2013. Histopathological diagnoses were simple (31) or aneurysmal (27) bone cysts, and nonossifying fibromas (4). The pathological fracture rate was 77.4 %. Surgical treatment was determined due to four criteria, including patient's skeletal maturity, localization and initial diagnosis of lesion, and amount of bone loss in the femoral neck and lateral proximal femur. Surgical procedure consisted of biopsy, curettage, bone grafting, and internal fixation when required. The median follow-up was 45 months (range 25-89 months).

RESULTS

Complete clinical recovery was achieved in 56 (90.3 %) patients between 4 and 8 months postoperatively; full weight-bearing and mobilization, without pain and limping, was possible. The median preoperative and postoperative last follow-up Musculoskeletal Tumor Society (MSTS) scores were 13.3 % (range 10-23.3 %) and 96.6 % (range 90-100 %), respectively (p < 0.0001). The pathological fractures were healed in 10 weeks on average (range 8-12 weeks). Fifty-seven (92 %) patients demonstrated complete or significant partial radiographic healing between 5 and 7 months that maintained throughout follow-up. Local recurrence was not observed, and only 1 (1.6 %) patient required reoperation for partial cyst healing. There were 5 (8 %) complications, 1 (1.6 %) of which required reoperation.

CONCLUSIONS

This treatment strategy can provide good local control and excellent functional and radiological results in the management of benign bone lesions of the proximal femur in children.

Unicameral Bone Cysts in the Humerus: Treatment Outcomes

BACKGROUND

Several treatment modalities have been described for the treatment of unicameral bone cysts (UBC). The aim of this study was to examine the outcome of various treatment modalities of UBC in a specific anatomic location, the humerus.

METHODS

This study is a retrospective case-only study of patients with humeral UBC with minimum follow-up of 1 year. Medical records and radiographs were assessed and UBC healing status was determined based on most recent follow-up radiographs and divided into 3 groups (healed, partially healed, and not healed). Descriptive statistics were utilized to summarize study outcome.

RESULTS

Sixty-eight patients (54 boys and 14 girls) with humeral UBC comprised the study population. Sixty-four cases (94.1%) presented with a pathologic fracture. Fifty-one cases were in the proximal metaphysis and 17 were in the diaphysis. Mean age at diagnosis was 9.2±3.7 years, and mean follow-up was 4.0±2.6 years. Twenty-five patients were treated with observation, 38 by injection (27 with steroids and 11 with bone marrow), and 5 by open surgery. Patients who underwent open surgery had relatively larger cyst length, width, and cyst index, and all healed or partially healed at last follow-up. UBC persistence was observed in 29% of diaphyseal and 27.5% of metaphyseal cysts. Of the 19 patients with persistence, 8 were treated with observation, 9 with steroid injection, and 2 with bone marrow injection. Inner wall disruption before injection was performed in 17 patients (24% did not heal), whereas 21 patients did not have inner wall disruption (33% did not heal). Twenty patients received >1 injection. Eleven patients complained of pain at the last visit (8 had a persistent cyst, 2 were partially healed, and 1 had a healed UBC).

CONCLUSIONS

Complete healing of humeral UBC is challenging to achieve irrespective of treatment modality. UBCs treated with open surgery tended to heal better. Unhealed cysts were more likely to be associated with pain.

LEVEL OF EVIDENCE

Level III-a retrospective comparative study.

"Three-in-One minimally invasive approach to surgical treatment of pediatric pathological fractures with wide bone loss through bone cysts: ESIN, curettage and packing with injectable HA bone substitute. A retrospective series of 116 cases."

INTRODUCTION

The outcome of pathological fracture due to large aggressive benign stage 3 Dormans and Flynn lesions [6] is often unsatisfactory and the rate of recurrence is high. No single technique has been considered safe and successful. Many Authors suggested curettage and bone grafting as the unique effective treatment in cases of large defect but, because of the invasive and complex nature of the operation (it needs a double-step procedure), it is not preferred. The purpose of this study is to examine the effectiveness of a minimally invasive treatment in one step through ESIN, curettage and packing with self-setting calcium phosphate cement.

PATIENTS AND METHODS

This is a retrospective study of 116 children admitted at the Division of Pediatric Orthopaedics Surgery of Santobono Children Hospital between 2006 and 2014 with a diagnosis of pathological fracture due to large aggressive ostheolytic benign lesions (stage 3 Dormans and Flynn). The size of bone loss was measured on the AP and ML radiographs and all the cysts with a caudo cranial extension from 5 to 8cm and with a medio lateral extension from 3 to 5cm were included. Mean time follow up 24 months was performed.

RESULTS

The three-in-one procedure was applied in all 116 patients. After two years of follow up, 113 patients were classified as healed and just 3 required 3 years to complete heal. No severe life threatening adverse effects or complications associated with the use of ESIN and injectable HA were recorded during the follow up period of 24-36 months. Fracture healing occurred in all cases within 4-6 weeks with adequate periosteal and endosteal callus formation. No second pathological fractures occurred in our series as well as no cysts reoccurred. Patients with humeral localizations showed a more rapid regain of muscular function and reestablishment of a complete range of motion.

CONCLUSIONS

The proposed three-in-one procedure has shown to be efficient, cost-effective, associated to high rates of definitive bone healing and low incidence of adverse effects.

Solitary bone cyst: a comparison of treatment options with special reference to their long-term outcome

Background

Solitary bone cysts (SBC) are benign, tumor-like lesions, which most frequently occur in the proximal metaphyseal-diaphyseal region of the humerus and femur of children and adolescents. The lack of a clear pathoetiology has impeded the development of treatment strategies. Up to date there is no consensus or official guideline for when and how treat SBC. The purpose of this study was to evaluate the effectiveness and the longterm clinical outcome of the treatment of SBC. Different techniques have been used dependant of the site of lesion, dimension, medical history and activity status.

Methods

135 skeletal immature patients with a solitary bone cyst were included. A follow up of 36 months or more was available for all patients. 22 patients were treated conservatively. All the other patients had at least one surgical intervention. The following four surgical treatment modalities were used: injection of methylprednisolon acetat (steroids), intramedullary nailing (IN), IN + steroids and curettage plus bone grafting.

Results

There was no significant difference between the treatment groups with respect to secondary fractures, function, pain, or complications. In the individual groups the failure rate after initial treatment was 36,6 % with steroids, 50 % with intramedullary nailing, 21,4 % with intramedullary nailing plus steroids and none in the remaining group.

Conclusion

Steroid injection remains a reliable method for treating solitary bone cysts owing to its low invasiveness. To prevent fractures and allow a full weight bearing, internal fixation in combination with methylprednisolon acetat injections seems to be the most favorable in weight bearing bones.

Treatment of Unicameral Bone Cysts of the Calcaneus: A Systematic Review

The calcaneus is the most common tarsal affected by unicameral bone cysts (UBCs); however, the treatment of calcaneal UBCs remains controversial. The purpose of the present systematic review was to evaluate the treatment modalities for calcaneal UBCs. A systematic review was performed using clinical studies of calcaneal UBCs with a minimum of 1 year of follow-up and level I to IV evidence. Ten studies with 171 patients (181 cysts) were selected. Heel pain and radiographic cyst consolidation were the primary outcomes. A series of Z tests were used to compare the outcomes in the nonoperative and operative groups, cannulated screw and bone augmentation groups, and autografting and allografting groups. All patients treated with open curettage and bone augmentation had significant improvements in heel pain (p < .001). Only 1.1% ± 1.0% of the cysts treated conservatively had healed on radiographs compared with 93.0% ± 13.0% of the cysts after surgery (p < .001). A greater percentage of patients treated with bone augmentation had preoperative heel pain and resolution of that pain than did patients treated with cannulated screws (p < .001). Autografting had a significantly greater percentage of radiographic cyst consolidation than did allografting (97.4% ± 11.1% versus 85.1% ± 15.8%, p < .001, Z = 3.5). Objective outcomes data on calcaneal UBCs are relatively sparse. The results of the present review suggest that open curettage with autograft bone augmentation is the most effective procedure. We would encourage future comparative clinical studies to elucidate differences in UBC treatment modalities.

Treatment of a unicameral bone cyst in a dog using a customized titanium device

A 4-year-old Shih-Tzu, referred for an enlarged left carpus, was diagnosed with a unicameral bone cyst. A customized titanium device was inserted into cystic lesion and fixed by titanium screws. Sufficient strength of the affected bone with the device inserted to maintain limb function was established after resection of contents of cystic lesion. There was no deterioration of the lesion of bone cyst, and acceptable function of the affected limb with no clinical signs of lameness was maintained during 36 months follow-up. The results of this study demonstrated that bone cyst curettage and use of a customized titanium device could provide an effective alternative treatment of huge lesion of unicameral bone cysts with the intent of preventing pathologic fractures.

Investigating a potential biological treatment to prevent pathological fractures caused by unicameral bone cysts in children under 8 years

INTRODUCTION

There is no consensus on when and how to treat unicameral bone cysts (UBCs), partly because of a lack of knowledge of the aetiology.

PURPOSE

To review the different treatment techniques for UBCs and to describe our results with a single injection of autogenous bone marrow (BM) mixed with demineralised bone matrix (DBM) in very young children.

PATIENTS AND METHODS

We reviewed five patients under the age of 8 years with UBCs treated by percutaneous aspiration and a single injection of BM associated with DBM. The cyst was located in the proximal humerus in four patients and in the proximal femur in one patient. Assessment of the need for surgery was based on the clinical and radiographic suspicion of new pathological fractures. The administration of a second injection, when necessary, was based on the surgeon's judgement regarding the risk of fracture. The mean follow-up after first injection was 41 months.

RESULTS

There were no complications related to the procedure, except a non-displaced fracture, which healed without problems. All patients were pain free and progressively resumed their activities without restriction until a new fracture occurred in two cases. According to Capanna's classification, only one case healed completely (grade 1), one lesion was classified as grade 2, and there were three recurrences at 11, 12 and 27 months after initial treatment (grade 3). The final outcome was treatment failure for three out of the five patients. Two patients were treated with a second injection and one patient is waiting for surgery.

CONCLUSION

A single injection of aspirated autogenous BM mixed with DBM in very young children with active UBCs at risk of fracture is very simple, comfortable and safe. Nevertheless, the results seem to be unpredictable and are probably more dependent on the natural evolution of the cyst than on the treatment. Further comparative studies with larger sample numbers are needed.

Does fracture affect the healing time or frequency of recurrence in a simple bone cyst of the proximal femur?

BACKGROUND

Studies have focused on intramedullary nailing of femoral simple bone cysts but have not clarified the recurrence frequency or management of recurrent cysts. In particular, the affect of pathologic fractures on cyst healing, recurrence, and complications of treatment have not been reported.

QUESTIONS/PURPOSES

We performed a retrospective comparative study to examine whether there were differences between simple bone cysts in the proximal femur nailed after pathologic fracture and those without pathologic fracture in terms of (1) healing time, (2) frequency and timing of recurrence, and (3) complications.

METHODS

From 1995 to 2005, 54 patients diagnosed with femoral simple bone cysts were treated and followed for a minimum of 8 years. Flexible nails were inserted in a retrograde fashion in 25 patients with fractures and 29 patients without fractures. The healing period, degree of radiographic consolidation based on the criteria of Capanna et al., recurrence frequency, and final bony abnormalities were analyzed. The mean followups were 107 months (range, 96-124 months) and 103 months (range, 96-140 months) in the groups with and without fractures, respectively. With the numbers available, a post hoc calculation showed that this study had 80% power to detect a difference of 7 months of healing time as significant with a probability less than 0.05.

RESULTS

With the numbers available, the mean healing period was not different between groups (25 versus 30 months in the groups with and without fractures, respectively; p = 0.16). Complete healing was observed at 19 versus 18 months, incomplete healing at 5 versus 8 months, and recurrence was observed in one and three patients in the groups with and without fractures, respectively. No differences were found in the distribution of healing grade based on the criteria of Capanna et al. A second surgery was performed using intramedullary nails in two patients with an open physis and compression hip screw fixation was performed in two patients with a closed physis. Finally, the recurrent cysts were classified as completely healed in three patients and incompletely healed in one.

CONCLUSIONS

Whether a pathologic fracture had occurred before surgical treatment, intramedullary nailing of femoral simple bone cysts resulted in reliable healing, and the frequency of recurrence did not differ. Because this was a retrospective study, the optimal treatment for recurred cysts after intramedullary nailing should be further investigated through a comparative or prospective study.

Treatment of unicameral bone cyst: systematic review and meta analysis

PURPOSE

Different treatment modalities have been utilized to treat unicameral bone cyst (UBC), but evidence has not been fully described to support one treatment over another and the optimal treatment is controversial. The aim of this quantitative systematic review was to assess the effectiveness of different UBC treatment modalities.

METHODS

We utilized Pubmed to isolate retrospective studies on patients with UBC who received any kind of treatment. The included studies needed to have a minimum sample size of 15 patients, and have provided data on radiographic healing outcome.

RESULTS

Sixty-two articles were selected for the meta-analysis from a total of 463 articles. The cumulative sample size was 3,211 patients with 3,217 UBC, and male to female ratio was 2.2:1. The summary or pool estimate of methylprednisolone acetate (MPA) injection resulted in a healing rate of (77.4 %) that was comparable to bone marrow injection (77.9 %). A higher healing rate was observed with MPA injection when inner wall disruption was performed. The pool estimate of bone marrow with demineralized bone matrix injection was high (98.7 %). UBC healing rate after surgical curettage was comparable whether autograft or allograft was utilized (90 %). UBC treatment with flexible intramedullary nails without curettage provided almost 100% healing rate, while continuous decompression with cannulated screws provided 89 % healing rate. Conservative treatment indicated a healing rate of 64.2, 95 % CI (26.7-101.8).

CONCLUSIONS

Active treatment for UBC provided variable healing rates and the outcomes were favorable relative to conservative treatment. Due to the heterogeneity of the studies and reporting bias, the interpretation of these findings should be handled with caution.

Treatment of unicameral bone cysts in pediatric patients with an injectable regenerative graft: a preliminary report

BACKGROUND

Multiple treatment modalities exist for unicameral bone cysts (UBC), including steroid injection, autologous bone marrow injection, mechanical decompression, intramedullary fixation, curettage, and bone grafting. All have their own potential limitations such as high recurrence rates, cyst persistence, need for multiple procedures, and prolonged immobilization. A minimally invasive regimen consisting of curettage, decompression, and injection of a calcium sulfate-calcium phosphate (CaSO4-CaPO4) composite has been utilized at our institution in an attempt to obtain optimal results for the treatment of UBCs in the pediatric population.

METHODS

We retrospectively evaluated 16 patients with pathologically confirmed UBC who were treated with curettage, decompression, and injection of a calcium sulfate-calcium phosphate composite between April 2006 and August 2010 at a single institution. The average age of the patients at time of surgical intervention was 9.4 years of age (range, 3 to 16 y). Average follow-up was 16 months (range, 6 to 36 mo). Radiographic healing, clinical outcomes, and complications were evaluated.

RESULTS

Final follow-up radiographs demonstrated healing in 93.7% (15 of 16) of patients after a single procedure. Complete healing was observed in 14 of 16 patients and partially healed with a defect in 1 of 16 patients. One patient had a persistent cyst but did not wish to receive further treatment. All patients returned to full activities including sports on average at 3.1 months (range, 1 to 6 mo) and were asymptomatic on most recent follow-up. No postoperative complications, including refracture, were observed.

CONCLUSIONS

Curettage, decompression, and injection of a calcium sulfate-calcium phosphate composite for UBC in the pediatric population demonstrates encouraging results with low recurrence rates and complications compared with conventional methods.

LEVEL OF EVIDENCE

Case series, Level of Evidence IV.

Flexible intramedullary nailing in simple bone cysts of the proximal humerus: prospective study for high-risk cases of pathologic fracture

We designed and evaluated a modified cyst index using the Picture Archiving and Communication System software for treating simple bone cysts of the proximal humerus by preventive intramedullary flexible nail insertion in symptomatic children or adolescents. From January 2007 to December 2009, cases with a cyst index of at least 4 were enrolled in the study. Of 20 total cases, 19 were prospectively followed-up for at least 2 years. The mean patient age was 10.6 years (range, 7-15 years) and the mean modified cyst index was 6.56 (range, 4.95-8.25). The mean cyst healing period was 8.7 months (range, 4-30 months) and the mean follow-up period was 31.05 months (range, 24-42 months). Seventeen lesions (89%) were classified as completely healed and two (11%) were classified as healed with residual radiolucency. In all cases, no angular deformity was found on the final follow-up radiograph. Therefore, preventive flexible intramedullary nail insertion before the occurrence of a pathologic fracture because of simple bone cysts with a modified cyst index of at least 4 in the proximal humerus is an excellent treatment option.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Percutaneous method of management of simple bone cyst

Introduction. Simple bone cyst or unicameral bone cysts are benign osteolytic lesions seen in metadiaphysis of long bones in growing children. Various treatment modalities with variable outcomes have been described in the literature. The case report illustrates the surgical technique of minimally invasive method of treatment. Case Study. A 14-year-old boy was diagnosed as active simple bone cyst proximal humerus with pathological fracture. The patient was treated by minimally invasive percutaneous curettage with titanium elastic nail (TENS) and allogenic bone grafting mixed with bone marrow under image intensifier guidance. Results. Pathological fracture was healed and allograft filled in the cavity was well taken up. The patient achieved full range of motion with successful outcome. Conclusion. Minimally invasive percutaneous method using elastic intramedullary nail gives benefit of curettage cyst decompression and stabilization of fracture. Allogenic bone graft fills the cavity and healing of lesion by osteointegration. This method may be considered with advantage of minimally invasive technique in treatment of benign cystic lesions of bone, and the level of evidence was therapeutic level V.

The role of osteoblast cells in the pathogenesis of unicameral bone cysts

PURPOSE

The pathogenesis of unicameral bone cysts (UBCs) remains largely unknown. Osteoclasts have been implicated, but the role of osteoblastic cells has, to date, not been explored. This study investigated the pathophysiology of UBCs by examining the interactions between the cyst fluid and human bone marrow stromal cells (hBMSCs) and the effect of the fluid on osteogenesis.

METHODS

Fluid was aspirated from two UBCs and analysed for protein, electrolyte and cytokine levels. Graded concentrations of the fluid were used as culture media for hBMSCs to determine the effects of the fluid on hBMSC proliferation and osteogenic differentiation. The fibrocellular lining was analysed histologically and by electron microscopy.

RESULTS

Alkaline phosphatase (ALP) staining of hBMSCs that were cultured in cyst fluid demonstrated increased cell proliferation and osteogenic differentiation compared to basal media controls. Biochemical analysis of these hBMSCs compared to basal controls confirmed a marked increase in DNA content (as a marker of proliferation) and ALP activity (as a marker of osteogenic differentiation) which was highly significant (p < 0.001). Osteoclasts were demonstrated in abundance in the cyst lining. The cyst fluid cytokine profile revealed levels of the pro-osteoclast cytokines IL-6, MIP-1α and MCP-1 that were 19×, 31× and 35× greater than those in reference serum.

CONCLUSIONS

Cyst fluid promoted osteoblastic growth and differentiation. Despite appearing paradoxical that the cyst fluid promoted osteogenesis, osteoblastic cells are required for osteoclastogenesis through RANKL signalling. Three key cytokines in this pathway (IL-6, MIP-1α, MCP-1) were highly elevated in cyst fluid. These findings may hold the key to the pathogenesis of UBCs, with implications for treatment methods.

Unicameral bone cyst of the scaphoid: a report of two cases

Unicameral bone cysts are benign, fluid-filled lesions that occur mostly in long bones (proximal humerus, 50-60%; femur, 30%) of male children aged 5 to 15 years. Occurrence in the scaphoid of an adult is rare. We report 2 such patients who presented with wrist pain, with and without a history of trauma. Both underwent curettage and bone grafting (harvested from the distal radius) and achieved good functional recovery.

Minimal invasive surgery for unicameral bone cyst using demineralized bone matrix: a case series

Background

Various treatments for unicameral bone cyst have been proposed. Recent concern focuses on the effectiveness of closed methods. This study evaluated the effectiveness of demineralized bone matrix as a graft material after intramedullary decompression for the treatment of unicameral bone cysts.

Methods

Between October 2008 and June 2010, twenty-five patients with a unicameral bone cyst were treated with intramedullary decompression followed by grafting of demineralized bone matrix. There were 21 males and 4 female patients with mean age of 11.1 years (range, 3–19 years). The proximal metaphysis of the humerus was affected in 12 patients, the proximal femur in five, the calcaneum in three, the distal femur in two, the tibia in two, and the radius in one. There were 17 active cysts and 8 latent cysts. Radiologic change was evaluated according to a modified Neer classification. Time to healing was defined as the period required achieving cortical thickening on the anteroposterior and lateral plain radiographs, as well as consolidation of the cyst. The patients were followed up for mean period of 23.9 months (range, 15–36 months).

Results

Nineteen of 25 cysts had completely consolidated after a single procedure. The mean time to healing was 6.6 months (range, 3–12 months). Four had incomplete healing radiographically but had no clinical symptom with enough cortical thickness to prevent fracture. None of these four cysts needed a second intervention until the last follow-up. Two of 25 patients required a second intervention because of cyst recurrence. All of the two had a radiographical healing of cyst after mean of 10 additional months of follow-up.

Conclusions

A minimal invasive technique including the injection of DBM could serve as an excellent treatment method for unicameral bone cysts.

Flexible intramedullary nailing for distal femoral fractures in patients with myopathies

PURPOSE

Distal femoral fractures are quite common in nonambulating patients with myopathies, as they present marked osteoporosis. The deterioration of preexisting knee flexion contracture is a known problem, as these fractures are usually angulated posteriorly. The goals of treatment are to reduce immobilization and bed rest to a minimum, prevent function loss, and prevent refracture. The aim of our work was to investigate if these goals can be achieved by an operative treatment with closed reduction and flexible intramedullary nailing (FIN).

METHODS

Six distal femoral fractures in four nonambulating patients with myopathies (three Duchenne muscular dystrophy and one nemaline myopathy) were treated with FIN between 2005 and 2011. Patient charts and radiographs were reviewed to determine if intra- or postoperative complications occurred and to detect the interval to wheelchair mobilization and hospital discharge. Pre- and postoperative knee flexion contracture was noted from the patient charts of our reeducation unit, where patients were already known preoperatively.

RESULTS

Wheelchair mobilization without further immobilization after an interval of 2-3 days was possible. No aggravation of knee flexion contracture was detected in our patient series. No complications associated to the operative treatment itself and no refractures in the follow up occurred.

CONCLUSION

Our experience showed that FIN is a low invasive and sufficiently stable osteosynthesis in such fractures. Left in place, nails will reinforce mechanical stability.

Percutaneous treatment of calcaneus fractures associated with underlying bone cysts

BACKGROUND

Calcaneal bone cysts with pathological fractures are rare. There is no clear consensus on their management with a few reports of open curettage, bone grafting and internal fixation in the treatment of pathological calcaneal fractures. No minimally invasive management has been reported before.

METHODS

We reviewed our experience in treating five patients with pathologic calcaneus fractures associated with pre-existing bone cysts who underwent percutaneous cyst curettage, fracture reduction, screw fixation and calcium sulfate cement injection between 2004 and 2009.

RESULTS

All of the pathologic fractures healed with satisfactory radiological results. There were no soft tissue complications or cyst recurrences. Partial weightbearing with plaster cast immobilization was allowed at 4 weeks postoperatively and full weightbearing was allowed at 6 weeks postoperatively.

CONCLUSION

This percutaneous technique provided a minimally invasive option for treatment of a calcaneal bone cyst with pathologic fracture.

Simple calcaneal bone cysts: a pilot study comparing open versus endoscopic curettage and grafting

This pilot study analysed the outcome of open versus endoscopic curettage and bone grafting for the treatment of simple calcaneal bone cysts. A total of 26 patients were evaluated into two equal groups: group 1 was treated with traditional open curettage and bone grafting and group 2 was treated with endoscopic curettage and percutaneous bone grafting. Cyst size, operating time, length of stay, time to healing, complications, further surgery and radiological healing were recorded and differences were statistically compared. The mean age of the patients was 22.9 years (18 to 28) and the mean follow-up was 28.7 months (24 to 36). There were no statistically significant differences in regard to age of patients, cyst size and the follow-up periods in the two groups. The operating time and mean length of stay of group 2 patients was significantly shorter than group 1 patients (p < 0.001). The time to healing was similar in the two groups. The overall success rates for groups 1 and 2 were 92.3% (12 of 13) and 100% (13 of 13), respectively, and there were no statistically significant differences regarding radiological healing. This pilot study suggests that endoscopic curettage and percutaneous grafting is a simple and safe form of treatment, with similar results to those following open treatment.

Unicameral bone cysts: comparison of percutaneous curettage, steroid, and autologous bone marrow injections

BACKGROUND

The purpose of this study was to compare the outcome of percutaneous curettage with intralesional injection of methylprednisolone and bone marrow for unicameral bone cysts (UBCs).

METHODS

This was a retrospective review of 46 children and adolescents with UBC treated with autologous bone marrow injection, methylprednisolone acetate injection or percutaneous curettage alone. Inclusion criteria were a radiological diagnosis of UBC and at least 24 months follow-up from the last procedure. Healing was determined using Neer/Cole 4-grades rating scale.

RESULTS

The 3 treatment groups were comparable with regard to age, sex, location of the cyst, and the number of procedures undertaken. At 2 years follow-up, the proportion of patients with satisfactory healing (Neer/Cole grades I and II) was greatest among those who underwent percutaneous curettage (70%) compared with bone marrow injection (21%) and methylprednisolone acetate injection (41%) (P = 0.03). We found no association between healing and age (P = 0.80) nor between healing and sex (P = 0.61).

CONCLUSIONS

These results suggest that mechanical disruption of the cyst membrane may be helpful in healing of cysts and that this technique may be preferred to simple intralesional injections.

LEVEL OF EVIDENCE

Level III.

Distance from the growth plate and Its relation to the outcome of unicameral bone cyst treatment

BACKGROUND

Interventions to treat unicameral bone cysts vary. Nonetheless, regardless of the intervention modality, the outcome is not certain. The purpose of this study was to determine if the distance between the growth plate and the cyst can be used to predict the outcome of the treatment.

METHODS AND MATERIALS

Retrospectively, we assessed the outcome of 39 interventions in nineteen children that were performed between 1994 and 2003. Seventeen different modalities of treatment were employed. There were three female and sixteen male patients. The average age was 8 years. Nine cysts were in the greater trochanter area, three were in the femoral capital area and seven were in the proximal humerus. According to the cyst's distance from the growth plate, at the intervention time, there were 18 cases within less than 2 cm and 21 cases of more than 2 cm.

RESULTS

Complete healing was achieved in 10 children (employing seven different modalities). In nine of them, the cysts were more than 2 cm away from the growth plate. In one child, the cyst was within less than 2 cm of the growth plate, however, treatment here involved epiphyseodesis.

DISCUSSION

This study confirmed that, regardless of intervention modality, complete healing was not achievable in those cysts that are within less than 2 cm of an active growth plate. Complete healing was possible in those cysts that are more than 2 cm away from the growth plate.

CONCLUSION

The 2-cm distance from the growth plate could be used as a predictor of treatment outcome of unicameral bone cysts.

Treatment of unicameral bone cyst: surgical technique

BACKGROUND

There is a variety of treatment modalities for unicameral bone cysts, with variable outcomes reported in the literature. Although good initial outcomes have been reported, the success rate has often changed with longer-term follow-up. We introduce a novel, minimally invasive treatment method and compare its clinical outcomes with those of other methods of treatment of this lesion.

METHODS

From February 1994 to April 2008, forty patients with a unicameral bone cyst were treated with one of four techniques: serial percutaneous steroid and autogenous bone-marrow injection (Group 1, nine patients); open curettage and grafting with a calcium sulfate bone substitute either without instrumentation (Group 2, twelve patients) or with internal instrumentation (Group 3, seven patients); or minimally invasive curettage, ethanol cauterization, disruption of the cystic boundary, insertion of a synthetic calcium sulfate bone-graft substitute, and placement of a cannulated screw to provide drainage (Group 4, twelve patients). Success was defined as radiographic evidence of a healed cyst or of a healed cyst with some defect according to the modified Neer classification, and failure was defined as a persistent or recurrent cyst that needed additional treatment. Patients who sustained a fracture during treatment were also considered to have had a failure. The outcome parameters included the radiographically determined healing rate, the time to solid union, and the total number of procedures needed.

RESULTS

The follow-up time ranged from eighteen to eighty-four months. Group-4 patients had the highest radiographically determined healing rate. Healing was seen in eleven of the twelve patients in that group compared with three of the nine in Group 1, eight of the twelve in Group 2, and six of the seven in Group 3. Group-4 patients also had the shortest mean time to union: 3.7 ± 2.3 months compared with 23.4 ± 14.9, 12.2 ± 8.5, and 6.6 ± 4.3 months in Groups 1, 2, and 3, respectively.

CONCLUSIONS

This new minimally invasive method achieved a favorable outcome, with a higher radiographically determined healing rate and a shorter time to union. Thus, it can be considered an option for initial treatment of unicameral bone cysts.