Humeral lengthening and deformity correction

Meeting report from the 3rd ISCBH-ERN BOND Achondroplasia Workshop on Long Bone Pathology in Children with Achondroplasia, Salzburg, Austria 22nd June 2024

A pre-meeting workshop on Long Bone Pathology in Children with Achondroplasia was held in Salzburg, Austria at the 11th International Conference on Children's Bone Health (ICCBH) 22-25 June 2024. There remains poor understanding and awareness amongst physicians managing achondroplasia of the underlying pathophysiology, radiology, natural history and orthopaedic procedures available for long bone deformities and restrictions. The structure of the workshop consisted of presentation of the results of a multinational patient survey on views of leg lengthening in achondroplasia, lectures, a debate and an interactive round table discussion. In total 150 attendees from 71 different cities and 31 countries were in attendance.

Bilateral humeral lengthening and deformity correction with hexapod external fixator in an achondroplastic patient: A case report

INTRODUCTION AND IMPORTANCE

Achondroplasia, a prevalent skeletal dysplasia, often results in limb asymmetry and functional limitations, typically managed surgically with bone lengthening techniques.

CASE PRESENTATION

We present the case of a 10-year-old girl with achondroplasia who underwent bilateral humeral lengthening using hexapod external fixators. The patient, previously treated for lower limb lengthening, exhibited significant upper limb shortening affecting daily activities. Surgical intervention involved two stages, employing two hexapod external fixators for precise correction and lengthening. Symmetrical lengthening of 6 cm in both humeri was achieved without major complications. Follow-up assessments revealed improved functionality and satisfactory outcomes, emphasizing the importance of addressing upper limb deformities in achondroplasia patients.

CLINICAL DISCUSSION

While humeral lengthening is less common than lower extremity lengthening due to historical concerns about neurovascular complications and functional implications, recent advancements highlight its potential benefits, particularly in achieving functional and aesthetic balance.

CONCLUSION

This case highlights the efficacy and safety of hexapod fixators in achieving multiplanar correction and functional improvement in upper limb lengthening. Further investigation should be carried out to study broader application in similar cases.

Anatomic consideration of the radial nerve in relation to humeral length for unilateral external fixation: a retrospective study using magnetic resonance imaging findings in korean

BACKGROUND

This study aimed to present a safe zone for distal pin insertion for external fixation using magnetic resonance imaging (MRI) images.

METHODS

All patients who took at least one upper arm MRI from June 2003 to July 2021 were searched via a clinical data warehouse. For measuring the humerus length, proximal and distal landmarks were set as the highest protruding point of the humeral head and lowermost margin of ossified bone of the lateral condyle, respectively. For children or adolescents with incomplete ossification, the uppermost and lowermost ossified margin of the ossification centers were set as proximal and distal landmarks respectively. The anterior exit point (AEP) was defined as the location of the radial nerve exiting the lateral intermuscular septum to the anterior humerus and distance between the distal margin of the humerus and AEP was measured. The proportions between the AEP and full humeral length were calculated.

RESULTS

A total of 132 patients were enrolled for final analysis. The mean humerus length was 29.4 cm (range 12.9-34.6 cm). The mean distance between the ossified lateral condyle and AEP was 6.6 cm (range 3.0-10.6 cm). The mean ratio of the anterior exit point and humeral length was 22.5% (range 15.1-30.8%). The minimum ratio was 15.1%.

CONCLUSION

A percutaneous distal pin insertion for humeral lengthening with an external fixator may be safely done within 15% length of the distal humerus. If pin insertion is required more proximal than distal 15% of the humeral shaft, an open procedure or preoperative radiographic assessment is advised to prevent iatrogenic radial nerve injury.

Monorail External Fixation in Humeral Lengthening and Deformity Correction with Glenohumeral Reduction: A Case Report

CASE

External fixation has an established use in humeral lengthening and deformity correction. An 11-year-old boy presented with left-sided humeral shortening, proximal varus deformity, and glenohumeral dislocation. Anatomical and functional corrections were achieved through innovative monorail external fixation, including bifocal osteotomies of the surgical neck and diaphysis proximal to the deltoid insertion.

CONCLUSION

Monorail external fixation with bifocal osteotomies of the surgical neck and diaphysis proximal to the deltoid insertion may improve the anatomical and functional outcomes in humeral shortening and proximal varus deformity with glenohumeral dislocation.

Derotational osteotomy and internal fixation of a 180° malrotated humerus: A case report

BACKGROUND

Humeral shaft fractures are relatively common in adults. Rotational malalignment is reported as one complication but severe rotational deformity of the humerus is extremely rare. To our knowledge, only three cases of symptomatic humeral malrotation have been reported. There are sparse literature reports of humeral reconstruction correction.

CASE SUMMARY

We present a case of extreme rotational deformity of the humerus (180°) after humeral shaft fracture. The patient complained of pain and difficulties with activities of daily living. In addition, she found the deformity cosmetically unacceptable. Therefore, she was searching for surgical correction. Neurolysis of the radial nerve followed by derotational osteotomy of the humerus and internal fixation were performed. Postoperatively, the patient demonstrated transient iatrogenic radial nerve palsy which recovered completely during postoperative follow-up. The Disabilities of the Arm, Shoulder, and Hand score improved from 55 preoperatively to 16 at the final 2-year follow-up.

CONCLUSION

Single-stage radial neurolysis, derotational osteotomy and stable fixation is a feasible option to improve anatomic and functional problems of severely malrotated humeral shaft fractures.

Adjustable bone plate: from bench to operating room

Background/aim

We have designed an adjustable bone plate (ABP) which allows bone shortening and lengthening after fixation, which is a property not present in any of the plate systems available today. The aim of the current study was to examine the new ABP's segmental bone transfer capability for the treatment of a segmental bone defect in an animal model.

Materials and methods

Five sheep had ABPs attached to 10 of their tibias and bone defects of 15 mm in size were created. The pinion mechanism was moved with a manual screwdriver at a rate of 1mm/day for 15 days starting 3 days postoperatively. The animals were euthanized 3 months postoperatively, and the defect site and the transferred segment were evaluated by radiological and histological examination.

Results

The radiological results revealed successful transfers of 14.6 ± 1.2 mm of bone segment on all tibia defects without any complications. The histological evaluation showed new bone formation in both the extension and the docking sites. No rupture or breakage was observed within the plates.

Conclusion

We have presented the potential of a new generation ABP for use in segmental bone transfer in an animal model as well as for future clinical applications.

What Are the Risks and Functional Outcomes Associated With Bilateral Humeral Lengthening Using a Monolateral External Fixator in Patients With Achondroplasia?

BACKGROUND

Many patients with achondroplasia experience functional impairments because of rhizomelic upper extremities (proximal limb shortening). Bilateral humeral lengthening may overcome these functional limitations, but it is associated with several risks, such as radial nerve palsy and insufficient bone regeneration. Only a few studies have reported on patient satisfaction and functional outcome after humeral lengthening in patients with achondroplasia. Furthermore, the reported numbers of adverse events associated with lengthening procedures using external fixators vary widely.

QUESTIONS/PURPOSES

(1) Does bilateral humeral lengthening with a monolateral external fixator in patients with achondroplasia reliably improve patient function and autonomy, and what proportion of patients achieved at least 8 cm of humeral lengthening? (2) What adverse events occur after bilateral humeral lengthening with monolateral external fixators?

METHODS

Between 2011 and 2019, 44 patients underwent humeral lengthening at our institution. Humeral lengthening was performed in patients with severe shortening of the upper extremities and functional impairments. In humeri in which intramedullary devices were not applicable, lengthening was performed with monolateral external fixators in 40 patients. Eight patients were excluded because they underwent unilateral lengthening for etiologies other than achondroplasia, and another four patients did not fulfill the minimum study follow-up period of 2 years, leaving 28 patients with bilateral humeral lengthening to treat achondroplasia available for analysis in this retrospective study. The patients had a median (interquartile range) age of 8 years (8 to 10), and 50% (14 of 28) were girls. The median follow-up time was 6 years (4 to 8). The median humeral lengthening was 9 cm (9 to 10) with a median elongation of 73% (67% to 78%) from an initial median length of 12 cm (11 to 13). To determine whether this treatment reliably improved patient function and autonomy, surgeons retrospectively evaluated patient charts. An unvalidated retrospective patient-reported outcome measure questionnaire consisting of nine items (with answers of "yes" or "no" or a 5-point Likert scale) was administered to assess the patient's functional improvement in activities of daily living, physical appearance, and overall satisfaction, such that 45 points was the highest possible score. The radiographic outcome was assessed on calibrated radiographs of the humerus. To ascertain the proportion of adverse events, study surgeons performed a chart review and telephone interviews. Major complications were defined as events that resulted in unplanned revision surgery, nerve injury (either temporary or permanent), refracture of the bone regenerate, or permanent functional sequelae. Minor complications were characterized as events that resolved without further surgical interventions.

RESULTS

On our unvalidated assessment of patient function and independence, all patients reported improvement at their most recent follow-up compared with scores obtained before treatment (median [IQR] 24 [16 to 28] before surgery versus 44 [42 to 45] at latest follow-up, difference of medians 20 points, p < 0.001). A total of 89% (25 of 28) of patients achieved the desired 8 cm of lengthening in both arms. A total of 50% (14 of 28) of our patients experienced a major complication. Specifically, 39% (11 of 28) had an unplanned reoperation, 39% (11 of 28) had a radial nerve palsy, 18% (5 of 28) had a refracture of the regenerate, and 4% (1 of 28) concluded treatment with a severe limb length discrepancy. In addition, 82% (23 of 28) of our patients experienced minor complications that resolved without further surgery and did not involve radial nerve symptoms. Radial nerve palsy was observed immediately postoperatively in eight of 13 segments, and 1 to 7 days postoperatively in five of 13 segments. The treatment goal was not achieved because of radial nerve palsy in 5% (3 of 56) of lengthened segments, which occurred in 7% (2 of 28) of patients. Full functional recovery of the radial nerve was observed in all patients after a median (IQR) of 3 months (2 to 5). Refractures of bone regenerates were observed in 11% (6 of 56) of humeri in 18% (5 of 28) of patients. Of those refractures, 1 of 6 patients was treated nonsurgically with a hanging cast, while 5 of 6 patients underwent revision surgery with intramedullary rodding.

CONCLUSION

Most patients with achondroplasia who underwent humeral lengthening achieved the treatment goal without permanent sequelae; nonetheless, complications of treatment were common, and the road to recovery was long and often complicated, with many patients experiencing problems that were either painful (such as refracture) or bothersome (such as temporary radial nerve palsy). However, using a subjective scale, patients seemed improved after treatment; nevertheless, robust outcomes tools are not available for this condition, and so we must interpret that finding with caution. Considering our discoveries, bilateral humeral lengthening with a monolateral external fixator should only be considered in patients with severe functional impairments because of rhizomelic shortening of the upper extremities. If feasible, internal lengthening devices might be preferable, as these are generally associated with higher patient comfort and decreased complication rates compared with external fixators.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Nine-year-long complex humeral nonunion salvaged by distraction osteogenesis technique: a case report and review of the literature

Background

Humeral nonunion with significant bone loss or shortening is uncommon and poses a complex clinical problem. We present a case of humeral nonunion with a large segmental bone defect treated with the distraction osteogenesis technique and remedy the radial nerve palsy produced during distraction osteogenesis by forearm tendon transfers. The reconstruction of upper limb function was achieved with satisfactory results. This case provides a referenceable alternative method for repairing large segmental bone defects due to complex nonunion of the upper extremity, as well as a remedy in the unfortunate event of radial nerve palsy, providing a reference and lessons learned for the treatment of similar cases and the management of possible complications.

Case presentation

A 31-year-old male patient experienced 9 years of hypertrophic nonunion due to an unreliable internal fixation. The radiographs showed the absence of bone bridging between the two fragments, loosening of the screws, and extensive osteolysis around the internal screws. The patient was treated with distraction osteogenesis. At the end of the distraction period, the patient unfortunately developed right radial nerve paresis, which was salvaged by forearm tendon transplantation, and finally reconstructed hand function and achieved bone union of the humerus.

Conclusion

Distraction osteogenesis, although not a panacea for all humeral nonunions with significant segmental bone loss, does offer a viable salvage procedure in this unusual and often complex clinical problem. When irreversible radial nerve palsy occurs during distraction, forearm tendon transfers can have a good clinical effect.

Age-related Outcomes and Complications of Osteodistraction in the Pediatric Upper Extremity: A Large Retrospective Single-center Study of 61 Cases

BACKGROUND

The study purpose was to assess: (1) the complication rate of osteodistraction in the pediatric upper extremity, its severity and relation to patient-specific and treatment-specific parameters, and (2) dedicated patient-reported outcome scores after these procedures.

METHODS

This retrospective study analyzed a chart of patients undergoing osteodistraction of the upper limb between 2003 and 2020. Demographics, distraction-specific parameters, healing index, and any complications graded according to the Sink grading scale (grades 1 to 5) were extracted. An additional phone interview was performed to assess patient satisfaction and functionality of the elongated limb using the Quick-DASH (Disabilities of Arm, Shoulder, and Hand) score.

RESULTS

This study included 61 cases from 48 individual patients. The mean age at the start of distraction was 11.5±3.6 years. The ulna was the most frequently lengthened bone, with 21 (34.4%) cases. Ninety-four complications were observed, with an average complication rate of 77.0%. Based on the Sink grading scale (1 to 5), grade 3 complications were most common (n=29; 47.5%) followed by grade 1 (n=14; 23.0%), 2 (n=14; 23.0%), and 4 (n=4; 6.6%). A significantly lower and thus better bone healing index was observed for the age category less than 10 years compared with the 14 to 18 years group (P=0.006). The average satisfaction was 4.2±1.0 points of 5. The mean Quick-DASH score was 14.1±12.5, indicating very good clinical outcomes.

CONCLUSIONS

Despite the occurrence of numerous complications, high patient satisfaction and good daily life functionality of the treated limb was observed. An age of more than 14 years at the beginning of therapy had a negative prognostic effect on bone healing during distraction. Thus, osteodistraction in the upper extremity may preferably be performed less than 10 years of age because of enhanced bone regeneration.

LEVEL OF EVIDENCE

Level IV-retrospective case series.

International recognition of the Ilizarov bone reconstruction techniques: Current practice and research (dedicated to 100th birthday of G. A. Ilizarov)

The Ilizarov method is one of the current methods used in bone reconstruction. It originated in the middle of the past century and comprises a number of bone reconstruction techniques executed with a ring external fixator developed by Ilizarov GA. Its main merits are viable new bone formation through distraction osteogenesis, high union rates and functional use of the limb throughout the course of treatment. The study of the phenomenon of distraction osteogenesis induced by tension stress with the Ilizarov apparatus was the impetus for advancement in bone reconstruction surgery. Since then, the original method has been used along with a number of its modifications developed due to emergence of new fixation devices and techniques of their application such as hexapod external fixators and motorized intramedullary lengthening nails. They gave rise to a relatively new orthopedic subspecialty termed “limb lengthening and reconstruction surgery”. Based on a comprehensive literature search, we summarized the recent clinical practice and research in bone reconstruction by the Ilizarov method with a special focus on its modification and recognition by the world orthopedic community. The international influence of the Ilizarov method was reviewed in regard to the origin country of the authors and journal’s rating. The Ilizarov method and other techniques based on distraction osteogenesis have been used in many countries and on all populated continents. It proves its international significance and confirms the greatest contribution of Ilizarov GA to bone reconstruction surgery.

Quality of life, physical functioning, and psychosocial function among patients with achondroplasia: a targeted literature review

PURPOSE

Achondroplasia (ACH) is the most common form of skeletal dysplasia, resulting in disproportionate short stature and medical complications. We review the literature on physical functioning, psychosocial function, and quality of life (QoL) in ACH individuals compared to average stature individuals or other short stature conditions. Studies that assess the association between these outcomes and height, limb length/lengthening surgery in ACH patients are also summarized.

MATERIALS AND METHODS

PubMed/MEDLINE and Embase were searched through April 2021. Study inclusion criteria were: (1) quantitative design; (2) study population consisting solely/mainly of ACH patients; (3) reports of physical functioning, psychosocial functioning, and/or QoL. Included studies were summarized separately for pediatric and adult populations.

RESULTS

Of 1664 records identified, 23 primary studies (sample size 8-437 participants) were included. Multiple tools were used across studies, including the generic PedsQL and SF-36 and height-specific QoLISSY.

CONCLUSIONS

The literature demonstrates that ACH patients experience limitations in physical functioning and poorer QoL outcomes compared to average stature people across the life span. This appeared to be at least in part due to disproportionate short stature. Future research to better characterize QoL in ACH patients will assist clinicians to better evaluate the effectiveness of management programs including novel interventions.IMPLICATIONS FOR REHABILITATIONPatients with achondroplasia experience limitations in physical functioning and poorer quality of life throughout their life course when compared to average statured individuals.Psychosocial issues are also heightened in adults with achondroplasia compared to average statured peers but are observed less frequently in children and adolescents with achondroplasia.The overall impact that limb lengthening has on physical functioning and QoL remains unclear, although there is some evidence that greater height or upper limb length may lead to an improvement in these parameters.Rehabilitation professionals should regularly assess physical functioning, psychosocial wellbeing, and quality of life in individuals with achondroplasia using condition-specific tools.

Upper Limb Lengthening in Achondroplasia Using Unilateral External Fixation

PURPOSE

The purpose of this study was to analyze the long-term results of humeral lengthening in achondroplastic patients and make suggestions on the most appropriate surgical technique to improve patient outcomes.

METHODS

Fifty-four humeral lengthening procedures performed in 27 achondroplastic patients were reviewed. Elongations were performed by means of callotasis with unilateral external fixation. Inclusion criteria were: achondroplastic patients under 17 years without prior arm operations and minimum follow-up of 36 months.

RESULTS

Fifty humeri in 25 patients (13 men and 12 women), aged between 9 and 17 years, met the inclusion criteria. Mean humeral lengthening was 8.82 cm (range: 5 to 10.5 cm), which represented an elongation of 54.80% (range: 46% to 63%) of the original length. The healing index was 0.91 months (range: 0.72 to 1.4 mo) per centimeter gained. Shoulder and elbow range of motion and stability were preserved in 47 limbs. Noncomplicated cases consistently experienced a significant functional improvement in the performance of activities of daily living such as putting on footwear and personal hygiene. Short-term complications included 11 pin-tract infections, 1 radial nerve neuropraxia, and 1 failure of the regenerated bone formation. None of these complications prevented from completion of treatment. Long-term complications included 2 cases of nonunion, 3 elbow flexion contractures, and 2 cases of psychological dissatisfaction, all of them in 4 patients. Factors associated with long-term complications were intraoperative fragment displacement and distal humeral osteotomy. No fractures of the regenerated bone were identified in the long term.

CONCLUSIONS

Callotasis with unilateral external fixation is a reliable and well-tolerated procedure for humeral lengthening in achondroplastic patients, with an acceptable complication rate. Guided fixator placement and a proximal humeral osteotomy are strongly recommended technical tips as they may help prevent complications and improve outcomes.

LEVEL OF EVIDENCE

Level IV-case series.

Adjustable bone plate: state of art

Background/aim

The success of treatment of bone fracture and defects are based on a proper contact and compression between the bone fracture fragments. Intraoperative manipulations such as bone compression or distractions are generally done in order to achieve this. However, none of the bone plates currently in routine use allow these manipulations after fixation to the bone, requiring refixation and repeated drilling, and screwing operations. Based on this shortcoming, we designed a novel adjustable bone plate (ABP) system which allows bone shortening and lengthening even after fixation to the bone surface. The aim of the paper is to clarify the unique properties of the novel bone plate.

Materials and methods

In this paper, the new generation adjustable bone plate applicability, design, indication, and new characteristics in addition to conventional bone plates with review of the literature were discussed and surgical technique was demonstrated in a saw bone model.

Results

This novel design allows for compression and distraction at the fracture ends post fixation as well as bone segment transfers.

Conclusions

The potential of the new generation ABP plate for use in bone compression, distraction, and the segmental bone transfer is a promising invention for clinical applications in the future.

Limb lengthening history, evolution, complications and current concepts

Limb lengthening continues to be a real challenge to both the patient and the orthopaedic surgeon. Although it is not a difficult operative problem, there is a long and exhausting postoperative commitment which can jeopardize early good results. I aim to review the history, evolution, biology, complications and current concepts of limb lengthening. Ilizarov's innovative procedure using distraction histeogenesis is the mainstay of all newly developing methods of treatment. The method of fixation is evolving rapidly from unilateral external fixator to ring fixator, computer assisted and finally lengthening intramedullary nails. The newly manufactured nails avoid many of the drawbacks of external fixation but they have their own complications. In general, the indications for limb lengthening are controversial. The indications have been extended from lower limb length inequality to upper extremity lengthening, including humeral, forearm and phalangeal lengthening. A wide range in frequency of complications is recorded in the English literature, which may reach up to 100% of cases treated. With developing experience, cosmetic lengthening has become possible using external or internal lengthening devices with an acceptable rate of problems.Level of evidence: V.

[Intramedullary upper arm lengthening]

The new technology of motorized intramedullary telescopic nails has simplified the treatment for upper limb lengthening surgery. Improved patient comfort, low infection rates and absence of fractures in the regenerated bone are contrasted by the limitations of the methods, such as a current maximum distraction of 5cm and the fact that they cannot be used when the growth plates are still open.

Innovative Technique in Extended Intramedullary Humeral Lengthening: A Case Report

CASE

Intramedullary humeral lengthening is still a very uncommon procedure to treat humeral limb length discrepancy (LLD). This approach has various advantages compared with external devices but is limited in its ability to lengthen bones because of the length of the telescopic nail. This case report describes a middle-aged patient with a short right humerus secondary to a childhood growth plate injury that was successfully lengthened with an off-label application of a tibial distracting device. Hereby, a novel treatment technique with unlocking, backwinding, and reinterlocking of the telescopic nail for extended humeral distraction was performed.

CONCLUSIONS

Extended intramedullary humeral lengthening with unlocking, backwinding, and reinterlocking of the nail is a cost-effective, minimally invasive procedure in cases of massive humeral LLD with limitations in the distraction capacity of the telescopic nail.

Complications and Outcomes Following Humerus Lengthening - An Illustrative: Case Report

Introduction

Upper limb physeal injuries are dealt with differently simply because they do not hinder with the functional abilities of an individual. Humerus lengthening was first attempted in 1978 after which it encouraged many surgeons to safely perform the procedure. Radial nerve palsy occurring as a complication of humeral lengthening was a major concern.

Case Report

We report a case of a 17-year-old girl with physeal arrest at the proximal physis of the humerus with etiology of post-trauma/post-infection. She presented with a shortening of 8 cm and restricted shoulder movements. We performed a lengthening of the humerus based on the principle of distraction osteogenesis. We used the paediatric limb reconstruction system to distract the corticotomy. However, postoperatively, she developed radial nerve palsy, despite our intraoperative precautionary measures. Distraction was started at 1mm/day. She then showed the progress of radial nerve recovery and full recovery was noted by 5 months post-operatively. The length of the distraction compression assembly had to be changed twice to longer sizes to accommodate the required amount of lengthening. After consolidation of regenerate was confirmed with serial radiographs, external fixator was removed. She was then maintained on a functional brace. We were able to achieve 8cm of lengthening following distraction, and the cosmetic appearance of the patient improved to the patient's and attenders' satisfaction.

Conclusion

Humeral lengthening can safely be performed. Careful insertion of the distal pins and performance of the corticotomy will ensure the safety of the radial nerve. Even if radial nerve palsy occurs after all precautions are taken, recovery can be expected.

Distraction osteogenesis of the humerus: a case of 100% humeral lengthening in a short duration without permanent complications

A 15-year-old boy with right humeral shortening underwent distraction osteogenesis with 1 mm/day lengthening. Preoperative Sauvegrain method showed skeletal maturity and lengthening did not account for future growth. Functional loading was encouraged 2 months before end of consolidation phase to hasten consolidation and fixator removal was done in the clinic without local anaesthesia at the patient's request 1 month earlier. A Sarmiento brace was made and compliance taught to the patient; however, the patient did not wear the brace and resumed body weight exercise weeks after removal of the fixator. Two months after removal of the external fixator, plain radiographs showed good recanalisation of the humeral shaft with no fracture or distortion. However, the left humerus grew and is now 1 cm longer than the right humerus. Nevertheless, the patient was satisfied with the upper limb length discrepancy.

Surgical technique and outcomes for bilateral humeral lengthening for achondroplasia: 26-year experience

BACKGROUND

Elongation in patients with achondroplasia provides better overall skeletal proportionality and significantly improves such individuals' access to their perineal region to self-manage personal hygiene. This paper describes our surgical technique and outcomes for bilateral humeral lengthening in achondroplasia patients over 26 years.

METHODS

Ours was a retrospective study of 55 patients with achondroplasia-related short stature, in whom bilateral humeral lengthening was performed from 1990 to 2016. We describe the surgical technique and analyze mean gain in humeral length, days using an external fixator, mean percentage of lengthening, external fixation index, type of callus, and complications. Pre- and postoperative radiographic measurements were obtained. Patients also were contacted by telephone and asked about their ability to perform peri-anal self-hygiene and about their overall satisfaction.

RESULTS

In total, 110 humeri were lengthened (28 males and 27 females) with medium elongation of 9.5 cm on the right and 9.6 cm on the left, while averaging 220 days in an external fixator. We observed 14 minor complications. There was no significant association between pin position and type of callus, and elongation most often external and in the presence of a straight callus. Before elongation, 77.1% of patients reported difficulties with perineal hygiene and 85.4% could not put their hands in their pockets. Upon completion of lengthening, 100% could perform both tasks and 94.5% were very satisfied.

CONCLUSIONS

Bilateral humeral elongation yields significant improvements in patient autonomy, with a relatively low complication rate and very high patient satisfaction.

Humeral lengthening and proximal deformity correction with monorail external fixator in young adults

PURPOSE

Several humeral lengthening or simultaneous deformity corrections through one osteotomy using various external fixators were reported, while literature regarding correction of shortening and proximal varus deformity is scarce. This retrospective clinical study evaluated the results of preforming an acute correction and delayed lengthening in young adults through two osteotomies using monorail external fixator.

METHODS

We report seven patients with various pathologies who underwent humeral proximal deformity correction and lengthening between 2009 and 2015. Pre-operative and post-operative clinical and radiographic data were collected. The mean follow-up time was 33.4 months (25-46 months).

RESULTS

The humeral neck-shaft angle improved from 97.9° (85-110°) to 138.6° (135-145°). The magnitude of lengthening achieved was average 7.6 cm (range, 6-10 cm) at an average healing index of lengthening of 30.2 days/cm (range, 27.7-35.4 days/cm). There was a significant increase in range of shoulder abduction, and active abduction improved from pre-operative 136.4° (range, 95-160°) to post-operative 166.4° (range, 150-180°). The DASH score improved significance from 23.29 ± 8.36 to 6.57 ± 3.65 (t = 4.848; p < 0.001).

CONCLUSION

Acute deformity correction and gradual lengthening with the monorail external fixator can be used for humeral shortening and proximal varus angular deformity. Functional improvement is expected after surgery and post-operative therapy.