|Year : 2017 | Volume
| Issue : 1 | Page : 37-44
Limb lengthening in pediatric patients with ollier's disease
Paige Goote1, Haluk Altiok2, Jennifer Beck3, Peter Smith2, Jeffrey Ackman2, Sahar Hassani2, Nikhil Kurapati4
1 Michigan State University College of Human Medicine, Grand Rapids, Michigan, USA
2 Department of Orthopedic Surgery, Chicago Shriners Hospital, Illinois, USA
3 Department of Orthopedic Surgery, David Geffen School of Medicine at UCLA, California, USA
4 Department of Orthopedic Surgery, Chicago Shriners Hospital, Illinois; Department of Orthopedic and Rehabilitation Engineering Center Marquette University/Medical College of Wisconsin, Milwaukee, Wisconsin, USA
|Date of Web Publication||15-Mar-2017|
Shriners Hospitals for Children, 2211, North Oak Park Avenue, Chicago, IL 60707
Source of Support: None, Conflict of Interest: None
Background: Ollier's disease is a non-hereditary skeletal disorder. Orthopedic management of limb length discrepancy could be complex given the nature of bone pathology, the significant amount of length discrepancy and the difficulty to predict it. The goal of the study is to identify the outcomes and complications associated with surgical management of limb length discrepancy. Methods: This is an IRB approved, retrospective review of patients with Ollier's disease who had limb lengthening. The age at the time of surgery, amount of total length discrepancy and discrepancy for each individual bone, amount of lengthening and as a ratio to the length of the bone itself, type of fixator, duration of the fixator, complications are recorded. Unpaired T-tests evaluated the effect of simultaneous versus single-bone lengthening and tibia vs. femur being lengthened on the external fixator index. One-way ANOVA test was used to evaluate the effect of osteotomy location on mean External Fixator Index (EFI). Results: 14 patients with 40 segmental limb lengthening procedures are identified. The mean LLD was 7.1 cm and mean amount of length gained was 7.8 cm. Follow up was minimum 2 years and maximum 18 years 2 months. The average fixator duration was 178.6 days. The average percent of lengthening through each bone was 19.2. The average EFI was 36.5 days/cm. There was no difference between tibia vs. femur and between simultaneous vs. single bone on EFI. There was no difference among osteotomy type. There were 3 cases of nonunion, one delayed union, 5 cases of premature consolidation. One case had fixation failure. There were 7 cases of knee stiffness of which 3 cases required surgery. Conclusions: Our study shows that Enchondromal bone appears to respond to lengthening with a structurally proper regenerate. Premature consolidation needs to be always kept in mind and appropriate adjustment should be made in the rate of lengthening.
Keywords: Limb lengthening, Ollier's disease, pediatric patients
|How to cite this article:|
Goote P, Altiok H, Beck J, Smith P, Ackman J, Hassani S, Kurapati N. Limb lengthening in pediatric patients with ollier's disease. J Limb Lengthen Reconstr 2017;3:37-44
|How to cite this URL:|
Goote P, Altiok H, Beck J, Smith P, Ackman J, Hassani S, Kurapati N. Limb lengthening in pediatric patients with ollier's disease. J Limb Lengthen Reconstr [serial online] 2017 [cited 2020 Sep 19];3:37-44. Available from: http://www.jlimblengthrecon.org/text.asp?2017/3/1/37/202208
| Introduction|| |
Enchondromatosis is a rare, heterogeneous skeletal disorder characterized by deformities in the metaphyses and diaphyses of long bones caused by benign hyaline cartilage tumors.,, Enchondromatosis includes several subtypes, of which Ollier's disease and Maffucci syndrome (enchondromatosis with cavernous hemangiomas) are the most common, whereas the other subtypes metachondromatosis, genochondromatosis, spondyloenchondrodysplasia, dysspondyloenchondromatosis, and cheirospondyloenchondromatosis are extremely rare. Ollier's disease is not inherited and occurs in 1 in 100,000 people. In most people with Ollier's disease, the mutations in the IDH1 or IDH2 genes are considered to be the cause.
The enchondromas appear early in childhood and display asymmetrical limb involvement, with one side being either exclusively or predominantly involved. Ollier's disease results in the disruption of longitudinal growth and structural integrity of bones that eventually leads to pathological fractures, progressive shortening of the involved extremity with resultant limb length discrepancy, and angular deformities.,, Limb length discrepancy could be significant early on and can be difficult to predict., 2, ,,,,,,, Orthopedic management of limb length discrepancy can be complex due to altered response of the bone as it is structurally and biologically compromised by the disease.
This is a retrospective study on patients with Ollier's disease who underwent one or more limb lengthenings over a period of time at one pediatric orthopedic specialty hospital. The goal of the study is to identify the outcomes and complications associated with the surgical management of limb length discrepancy in children with Ollier's disease as well as the unique factors associated with success and failure in this peculiar disorder.
| Materials and Methods|| |
This is an IRB-approved, retrospective chart and radiographic review of patients with Ollier's disease who had limb lengthening between 1990 and 2015. Seventeen patients were identified who underwent the surgical procedure; however, only 14 patients (6 females and 8 males) had available charts and radiographs for review. All patients were seen at the same hospital.
Of the 14 patients, 13 patients had only lower limb involvement and 1 patient had both upper and lower limb involvement. These 14 patients had a total of 42 segmental limb lengthening procedures with simultaneous deformity correction as needed (40 lower and 2 upper extremity lengthenings). In this study, only lower extremity data are included. One of the 14 patients developed a hemangioma later in his adolescence, making him a case of Maffucci syndrome.
The average age at the time of first lengthening was 8 years, 1 month, while the average age for all lengthening surgeries was 9 years, 9 months. Average follow-up was 10 years, 11 months (minimum 2 years to maximum 18 years, 2 months.) Lengthening began 1 week after application of the external fixator. The time for safe removal of the external fixator was decided by the radiological confirmation of regeneration of at least three cortices after the desired length had been reached. Patients were casted after frame removal and followed up in clinic.
A total of 35 ring external fixators (33 Ilizarov and 2 Taylor Spatial Frames), 5 unilateral external fixators (in 4 cases, unilateral fixators were used for lengthening over intramedullary nails) were used for the lengthenings. The choice of external fixator was based on the surgeon's experience and comfort level and the demand by the deformity and length deficiency.
The following parameters were measured for each patient's segmental lengthenings: age at the time of surgery, amount of total length discrepancy and discrepancy for each individual bone, amount of lengthening in centimeters and as a ratio to the length of the bone itself, type of fixator, length of duration of the fixator, location of the corticotomy in relation to the enchondromas in the bone (intralesional, transitional, and extralesional), and location of fixation points (intralesional and extralesional).
Lascombes' classification of complications after progressive long bone lengthening was used. The classification measures the outcome of treatment based on three criteria that form the basis of the contract: The gain in length, projected treatment duration, and the maintenance of musculoskeletal function. This classification system also includes four grades: grade I: The contract is fulfilled on all three criteria, procedures are undertaken under local anesthesia, and/or medical treatments are necessary, but no intervention under general anesthesia is taken. Grade II: The contract is also fulfilled on all three criteria, but unscheduled interventions under general anesthesia are necessary (Grade IIa - these procedures are undertaken before the end of lengthening program, or Grade IIb - after the end of program). Grade III: Pursuing treatment is needed beyond the planned period to obtain bone union, but at term, no alteration of function is observed (Grade IIIa - the length gain is ≥75% of the initial objective and Grade IIIb - <75%). Grade IV: Sequelae exist at the final evaluation with loss of function (Grade IVa - the gain is >75%, and Grade IVb - <75%).
For each segmental lengthening, the external fixation index (EFI) was measured. The EFI ratio is defined as the entire duration of external fixation divided by the length gained in cm.
Descriptive statistics including means and standard deviations were calculated for age, initial limb length discrepancy, amount of surgical length gained, and EFI. Frequencies of lengthening at tibia versus femur, simultaneous versus single bone lengthening, and osteotomy location were also calculated. We used unpaired t-tests to evaluate the effect of simultaneous versus single bone lengthening as well as the bone (tibia vs. femur) being lengthened on EFI. We also used a one-way ANOVA to evaluate the effect of osteotomy location (intralesional vs. transitional vs. extralesional region) on mean EFI. The level of significance was set to P < 0.05. The statistical package used was SPSS version 24 (IBM, Armonk, NY, USA).
| Results|| |
Overall, the mean limb length discrepancy before surgery was found to be 7.1 cm. The mean amount of length gained was 7.8 cm. Lengthening the bone beyond the initial discrepancy is done in many cases to accommodate for the final predicted discrepancy. [Figure 1] and [Figure 2] show patients who had undergone simultaneous femur and tibia lengthening and deformity correction with Taylor Spatial Frame.
|Figure 1: (a) A 6-year, 7-month-old boy with an initial discrepancy of 8.5 cm presurgery - preoperative. (b) Subject with external fixature. (c) Postoperative - subject following removal of external fixator|
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|Figure 2: (a) A 13-year-old girl with Ollier's disease. Application of circular external fixator for simultaneous femur and tibia lengthening. (b) 9 months after the application of the frame due to the persistence of nonunion of the tibia injection of iliac crest bone marrow is performed. (c-e) 12 months after the index surgery due to persistent nonunion, patient underwent ex-fix removal and iliac crest bone graft application and plating. Final X-ray shows complete healing and hardware removed|
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The average length of time the fixators were attached was 178.6 days (range 60–405 days) for all forty segmental lengthenings. The average percent of lengthening through each bone for all cases was 19.2%. The average EFI was 36.5 days/cm for all segmental lengthenings. It was 23.9 days/cm for the combination of unilateral external fixators with intramedullary nails, 41.8 days/cm for simultaneous femur and tibia lengthening with circular external fixators, and 31.1 days/cm for cases where each bone lengthened separately with circular external fixators. Further detailed information with regard to each individual segmental lengthening is listed in [Table 1],[Table 2],[Table 3].
For the EFI, there was no difference between tibia versus femur (t-test: 37.08 ± 24.2 vs. 41.02 ± 10.6, P = 0.544) and no difference between simultaneous versus single bone on EFI (t-test: 41.1 ± 20.0 vs. 31.9 ± 8.9, P = 0.218). There was also no difference among osteotomy type (ANOVA: intralesional 36.71 ± 20.9, transitional 22.13 ± 4.2, and extralesional 45.9 ± 17.6, P = 0.30) on EFI.
The complications encountered were numerous, and they are classified as proposed by Lascombes  based on their impact on the outcome of treatment as defined by the gain in length, duration of treatment, and function and shown in [Table 4].
There was one case of fixation failure within the study group despite most fixation locations being within pathologic bone. In this case, fixation wire through fibula pulled out which needed a revision of the frame.
Three patients (three cases) had nonunions which required grafting. Two cases of nonunions occurred in the femur. In the first case, the bone was lengthened up to 25%, and in the other case, up to 10% of its length. The third case involved a tibia lengthening up to 16% of its length. The second femoral case with 10% lengthening required irrigation and debridement and grafting with a bone substitute (Osteoset). The other cases had no sign of infection and they also required different combinations of iliac crest bone autograft, allograft, bone substitute (Osteoset), and internal fixation to promote healing.
There was one documented delayed healing through a femur lengthening (26% lengthening), which required grafting with bone substitute (Osteoset), 5 months after the frame application.
Four patients (five cases) encountered premature consolidation with two requiring repeat corticotomy and three requiring closed osteoclasis. All these cases happened through femur though it was both femur and fibula in one case where a simultaneous lengthening of femur and tibia was undertaken.
In 7 cases of limb lengthening (6 patients), knee joint stiffness was encountered. In six cases, external fixator frames were crossing knee joint for simultaneous femur and tibia lengthening and/or deformity correction. In one case, it was isolated femur lengthening. Physical therapy was all needed for four cases, whereas in three cases, patients needed surgery. Surgery consisted of adhesiolysis and manipulation under anesthesia in all three cases. One case later on needed additional quadricepsplasty. No joint subluxation or dislocation happened in our study group.
Besides common pin site infections, there were serious infections which needed aggressive treatment. In one case, irrigation and debridement were needed for surgical site infection. In another case, where the bone was lengthened over a nail with a unilateral external frame, the rod was removed because of a late infection after the lengthening was over and the bone had healed. In one case, the pin site infection and osteolysis needed early removal of the frame. In one case, infection at the surgical site lead to infected nonunion of the bone.
One patient had a fracture through femur 5 months postfixator removal requiring a return to the operating room for a rush rod placement. One patient had an overlengthening of the bone which was corrected while still in the fixator. In five cases in five patients, ankle equinus contracture developed. Tendo-Achilles lengthening was performed in three of these five cases.
One patient developed a low-grade chondrosarcoma through the proximal femur which was resected. The chondrosarcoma was not located at a fixation or osteotomy site.
| Discussion|| |
Limb length discrepancy is a common finding in Ollier's disease.,,,, Concerns regarding limb lengthening with patients with Ollier's disease include biological response of the bone to the lengthening process i.e. structural quality of the regenerated bone, healing response, time, and pathological fractures but also the ability of successful fixation/anchoring of the external fixator to the bone during the process of lengthening.,,,,,,,,,,,
The site of the corticotomy, the response of the diseased bone to the callus distraction, and lengthening and the quality of the regenerate bone have been a subject of concern and debate.,,,,,, Watanabe  reported seven osteotomies performed intralesionally and in only one of seven cases, the regenerate tissue appeared to look like normal bone. Contrary to this, Madan. performed all osteotomies through the lesion and all formed normal regenerate bone. D'Angelo  suggested that the corticotomy be performed at the junction between the healthy and pathological tissue. In their study of 23 cases in 9 patients, all went on to heal with normal regenerate tissue. Märtson  and Jesus-Garcia  with a needle biopsy done through the regenerate showed that the tissue was replaced with normal bone. Pandey  referring to the studies done by Ilizarov  and Aronson  indicated that osteogenesis under tension occurs by intramembranous rather than by enchondral ossification which may explain why the regenerate tissue turns into regular bone. In our study, we had 20 intralesional, 6 transitional, and 14 extralesional corticotomies. The level of corticotomy was chosen either based on the apex of deformity or on a suitable level after the external fixator is anchored to the bone. Based on the radiographic assessment, the regenerated bone looked normal in our cases; however, there were no histologic studies to confirm this impression.
Despite the concern of poor quality of the diseased bone, the healing response for fractures and limb lengthening has been remarkably good. Shapiro  reported multiple incidences of pathological fractures which readily healed with conservative management. Limb lengthening has a similar healing response. In our study, fixator duration, percentage lengthening, EFI with or without IM nails. This value was quite similar to the values of 32.5 days/cm reported by Madan  and 31.6 days/cm for femur and 35.7 cm/day for the tibia reported by Popkov  where similar external fixator and techniques were used. When compared to the literature where lengthening for different heterogeneous underlying pathologies was done with Ilizarov technique, we see similar numbers: 35 days/cm by Bonnard, 22.3 days/cm for femoral lengthening by Stanitski, 40.8 days/cm by Glorion, and 49.3 days/cm by Tsuchiya.
When we looked at the external fixator index values based on the site of corticotomy, the results were quite similar, and the site of corticotomy does not appear to be a factor in the healing response. In our study, the EFI was 36 days/cm for intralesional, 37.5 days/cm for transitional, and 39.7 days/cm for extralesional corticotomies. Watanabe  reported intralesional corticotomy yielded EFI values of average 39.7 days/cm and extralesional corticotomy yielded EFI values of average 30.8 days/cm even though difference of these values was not statistically significant. For our study, there was also no statistical difference among corticotomy types on the EFI.
Premature consolidation has been considered to be a problem during limb lengthening with Ollier's disease. Paley  stated that premature consolidation is most commonly seen in patients with Ollier's disease but did not give any number of patients or cite any other study. Myers  reporting in patients with skeletal dysplasia, noticed the tendency for hypertrophic bone regeneration in patients with achondroplasia and Ollier's disease. However, there was no case of premature consolidation in his group of patients with Ollier's disease. Increased rate of distraction was suggested to manage this problem. Madan  described three cases of premature consolidation in a group of ten patients. Tellisi  described premature consolidation in a case study with humeral lengthening. In our study group, we had five cases of premature consolidation in forty cases. All of the cases were through femurs (in one case, it was both femur and fibula). Latency period after surgery, rate of distraction, level of osteotomy, and patient characteristics may play a role in this problem.
The other end of the spectrum of bone healing is delayed union or nonunions. In our study, we had three nonunions (two femur one tibia) and delayed union (femur) which required additional surgery for bone grafting. Nonunion has been described for a case of ulnar lengthening in a patient with Ollier's disease by Kolodziej  Given the retrospective nature of our study, teasing out the factors responsible for nonunions was difficult. In one case, it was an infected nonunion. The amount of lengthening was up to 26% (delayed union), 25%, 10% of the length of femur, and 16% for the tibia. The reasons for these nonunions could be multifactorial including traumatic corticotomy, instability of the frame, initial diastasis, too rapid distraction, infection, malnutrition or multiple lengthenings through the same bone.
Pathological fracture at the regenerate bone is a concern given the lengthening done within or around the diseased bone. In our study group of forty cases, and in the study by Jesus-Garcia  with 18 cases, there was one case of pathological fracture each after frame removal. Popkov  compared two separate group of patients with Ollier's disease with limb lengthening, one group with external fixator only and the other group with a combination of external fixator and elastic stable intramedullary nail. There were three cases of deformities at the regenerate site and three cases of pathological fractures in the enchondroma region after frame removal in the group with external fixator only (out of 57 cases). In the combo group, seven cases had no pathological fractures after frame removal. In general, the regenerate bone appears to be sufficiently strong after lengthening is completed with no major long-term sequela.
Given the poor quality of diseased bone, proper anchoring of the external fixator to the bone, and loss of fixation has been a concern.,,,, Shapiro  suggested the lengthening to be done through diaphysis because of the concern of poor fixation into the diseased bone. Addition of extra fixation points to the diseased bone has been advocated.,, Baumgart  had a case presentation where he successfully utilized an all-inside technique with a fully implantable motorized nail with no complications. There was one case of fixation failure - wire pull out from proximal fibula - within our study group despite most fixation points being within the pathologic bone. Despite these general concerns, with the utilization of modern techniques of lengthening based on Ilizarov method with ring and unilateral external fixators and extra fixation points added as needed, fixation failure has not been an issue in the current literature.,,,,,,
Joint stiffness appears to be a common issue in many studies. This could be due to persistent muscle contracture, duration of immobilization of the joint, amount of lengthening, and related pressure through the joint surface. Madan  and Jesus-Garcia  described a total of three cases out of 49 with knee joint stiffness which persisted after the final follow-up. Myers, in his study of limb lengthening in skeletal dysplasia of various etiologies, described ten cases of knee stiffness out of 26 patients and out of ten cases, only one had Ollier's disease. We had seven cases of knee joint stiffness in 6 patients. In 3 cases, surgery was needed to address the problem. Except one case, in all other cases, the frame extended from the femur to the tibia crossing the knee joint. In 4 cases, it was the first time lengthening, whereas in 2 cases, it was a second time lengthening, and in one case, it was the third time lengthening. Vigorous, aggressive therapy, appropriate soft tissue tension management with bracing, utilization of the hinges across the joints, and minimizing the time of the frame applied can help to diminish the incidence of this problem. In our study, unilateral external fixator over intramedullary nails minimized. Substantially reduced duration of external fixation was the case in the study group by Popkov  where the ring fixators were applied over intramedullary elastic nails compared to a group where only the ring fixators were used. In the study by Curran, when compared with single bone lengthening, the time spent in the Ilizarov frame was significantly less for the patients undergoing simultaneous ipsilateral femoral and tibial lengthening.
Although sarcomatous changes are common in Ollier's disease, patients over their lifetime, this has not been reported at the site of limb lengthening., In our group, one patient went on to develop a low-grade chondrosarcoma of the proximal femur on the side where she had limb lengthening. However, the location of the sarcoma was not in an area of lengthening.
Our study shows that limb lengthening in patients with Ollier's disease is a complex demanding procedure, but successful results are achievable. A considerable amount of leg length discrepancy could happen even at early ages, and the patients may go through limb lengthening many times through their lifetime. We agree D'Angelo  study that the bone in Ollier's disease may not be predictable in terms of its behavior, and this may complicate the efforts of calculating the final leg length discrepancy. Enchondromatous bone appears to respond to lengthening with a structurally proper regeneration. Location of the corticotomy site whether intralesional or extralesional does not appear to have an impact on healing response. Modern external fixators with wire and pin fixation with or without intramedullary nail will provide the appropriate means of lengthening. Premature consolidation needs to be always kept in mind, and appropriate adjustment should be made in the rate of lengthening. Nonunion though unusual in these patients, can occur. In patients with simultaneous femur and tibia lengthening, the knee joint should be aggressively rehabilitated to prevent stiffness with frames that allow a range of motion.
Financial support and sponsorship
This study was financially supported by The Shriners Lemieux Summer Internship Grant.
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4]