Evaluation of simultaneous bilateral femoral distraction osteogenesis with antegrade intramedullary lengthening nails in achondroplasia with rhizomelic short stature: a retrospective study of 15 patients with a minimum follow-up of 2 years.

BACKGROUND AND PURPOSE: Bilateral femoral distraction osteogenesis in patients with achondroplasia is insufficiently reported. We aimed to perform the first study that exclusively analyzed simultaneous bilateral femoral distraction osteogenesis with motorized intramedullary lengthening nails via an antegrade approach in patients with achondroplasia focused on reliability, accuracy, precision, and the evolving complications. PATIENTS AND METHODS: In this retrospective singlecenter study we analyzed patients with achondroplasia who underwent simultaneous bilateral femoral lengthening with antegrade intramedullary lengthening nails between October 2014 and April 2019. 15 patients (30 femoral segments) of median age 14 years (interquartile range [IQR] 12-15) were available for analysis. The median follow-up was 29 months (IQR 27-37) after nail implantation. RESULTS: The median distraction length per segment was 49 mm (IQR 47-51) with a median distraction index of 1.0 mm/day (IQR 0.9-1.0), and a median consolidation index of 20 days/cm (IQR 17-23). Reliability of the lengthening nails was 97% and their calculated accuracy and precision were 96% and 95%, respectively. The most common complication was temporary restriction of knee range of motion during distraction in 10 of 30 of the lengthened segments. 1 patient was treated with 2 unplanned additional surgeries due to premature consolidation. CONCLUSION: The method is reliable and accurate with few complications.

[Options and limits of leg length correction in paediatric orthopaedics]. / Möglichkeiten und Grenzen der Beinlängenkorrektur in der Kinderorthopädie.

For paediatric orthopaedic surgeons treating leg length discrepancy, knowledge of the available procedures and their options and limits is just as important as mastery of the very different surgical methods and implants, as well as the possible complications, in order to be able to advise and treat the children and adolescents and their parents comprehensively and in the best interests. Both the growth inhibiting procedures and the complex bone lengthening procedures require a great deal of experience to successfully guide patients and families through what is often a lengthy and sometimes complicated treatment process. Careful preoperative indications and planning, precise surgical techniques with suitable instruments and implants, and attentive postoperative check-ups are mandatory prerequisites for the desired therapeutic success.

Preliminary results of two novel devices for epiphysiodesis in the reduction of excessive predicted final height in tall stature.

BACKGROUND: In the treatment of tall stature, the reduction of excessive predicted final height can either be achieved by hormonal treatment or surgically by temporary (tED) or permanent (pED) epiphysiodesis. The present study evaluates the preliminary results of two novel devices for tED and pED around the knee to reduce the predicted final height. MATERIALS AND METHODS: A retrospective analysis was performed to evaluate the clinical and radiographic outcome after bilateral epiphysiodesis for the treatment of tall stature. A cohort of 34 patients (16 girls, 18 boys) who underwent either tED or pED between 2015 and 2020 were eligible for analysis based on the electronic patient records and picture archiving and communication system of our orthopaedic teaching hospital. tED was conducted in 11 patients (32%) through bilateral implantation of four RigidTacks™ (Merete, Berlin, Germany) around the knee. Twenty-three patients (68%) received pED, performed with an EpiStop™ trephine (Eberle, Wurmberg, Germany). The mean overall follow-up time was 2.9 years. RESULTS: The mean age at surgery was 12.3 years in girls and 13.2 years in boys. Patients had a mean body height of 175.2 cm in girls and 184.7 cm in boys at surgery. The mean predicted final height was 191.4 cm in girls and 210.4 cm in boys. At the last follow-up, 26 patients (76.5%) had achieved skeletal maturity. The mean height of skeletally mature patients was 187.2 cm in girls and 198.5 cm in boys. A mean reduction of the predicted final height of 5.9 cm in girls and 8.7 cm in boys was achieved, corresponding to a reduction in remaining growth of 46% in girls and 38% in boys. Secondary frontal plane deformities of the knee were detected in 5/11 patients (45.5%) in the tED group and 1/23 treatments (4.3%) in the pED group. CONCLUSIONS: tED and pED have both proven to be efficient at achieving growth inhibition to reduce excessive predicted height. However, tED has been associated with an increased risk of secondary angular deformities of the knee. Furthermore, the risk of implant-related complications and the necessity of a subsequent surgical intervention for implant removal have led our study group to abandon tED when treating tall stature. Long-term results of both procedures are pending.

Surgeons' non-transparent facemasks challenge the physician-patient relationship in the orthopedic outpatient clinic of a tertiary university hospital during the COVID-19 pandemic: a prospective cohort study of 285 patients.

Background and purpose - Facemasks play a role in preventing the respiratory spread of SARS-CoV-2, but their impact on the physician-patient relationship in the orthopedic outpatient clinic is unclear. We investigated whether the type of surgeons' facemask impacts patients' perception of the physician-patient relationship, influences their understanding of what the surgeon said, or affects their perceived empathy. Patients and methods - All patients with an appointment in the orthopedic outpatient clinic of a tertiary university hospital during the 2-week study period were included. During consultations, all surgeons wore a non-transparent (first study week) or transparent facemask (second study week). Results of 285 of 407 eligible patients were available for analysis. The doctor-patient relationship was evaluated using the standardized Patient Reactions Assessment (PRA) and a 10-point Likert-scale questionnaire ranging from 0 (strongly disagree) to 10 (strongly agree). Results - A non-transparent facemask led to more restrictions in the physician-patient communication and a worse understanding of what the surgeon said. Patients' understanding improved with a transparent facemask with greatest improvements reported by patients aged 65 years and older (non-transparent: 6 [IQR 5-10] vs. transparent: 10 [IQR 9-10], p < 0.001) and by patients with a self-reported hearing impairment (non-transparent: 7 [IQR 3-7] vs. transparent: 9 [IQR 9-10], p < 0.001). The median PRA score was higher when surgeons wore a transparent facemask (p= 0.003). Interpretation - Surgeons' non-transparent facemasks pose a new communication barrier that can negatively affect the physician-patient relationship. While emotional factors like affectivity and empathy seem to be less affected overall, the physician-patient communication and patients' understanding of what the surgeon said seem to be negatively affected.

The Bateman-Type Soft Tissue Reconstruction around Proximal or Total Humeral Megaprostheses in Patients with Primary Malignant Bone Tumors-Functional Outcome and Endoprosthetic Complications.

We aimed to evaluate the functional outcome and endoprosthetic complications following the Bateman-type soft tissue reconstruction around proximal or total humeral replacements in patients undergoing resection of a primary malignant bone tumor. Between September 2001 and December 2018, a total of 102 patients underwent resection of a primary malignant bone tumor and subsequent reconstruction with a modular humeral megaprosthesis in our department. Fifteen (15%) of these patients underwent a Bateman-type soft tissue reconstruction and were included in this retrospective study. The median Musculoskeletal Tumor Society (MSTS) score was 21, the median Toronto Extremity Salvage Score (TESS) was 70, and the median American Shoulder and Elbow Surgeons (ASES) score was 72. Fifty-three percent (8/15) of all patients required a revision surgery after a median time of 6 months. There were 2 soft tissue failures, 3 infections and 3 tumor recurrences. The revision-free implant survivorship amounted to 53% (95% confidence interval (CI) 28-81) after 1 year and 47% (95% CI 22-73) at last follow-up. The Bateman-type reconstruction is a feasible option for soft tissue reconstruction but functional outcome is overall limited and the risk for revision surgery within the first postoperative year is high.

Invasive diagnostic and therapeutic measures are unnecessary in patients with symptomatic van Neck-Odelberg disease (ischiopubic synchondrosis): a retrospective single-center study of 21 patients with median follow-up of 5 years.

Background and purpose - Van Neck-Odelberg disease (VND) is a self-limiting skeletal phenomenon characterized by a symptomatic or asymptomatic uni- or bilateral overgrowth of the pre-pubescent ischiopubic synchondrosis. It is frequently misinterpreted as a neoplastic, traumatic, or infectious process, often resulting in excessive diagnostic and therapeutic measures. This study assessed the demographic, clinical, and radiographic features of the condition and analyzed diagnostic and therapeutic pathways in a large single-center cohort.Patients and methods - We retrospectively analyzed 21 consecutive patients (13 male) with a median age of 10 years (IQR 8-13) and a median follow-up of 5 years (IQR 42-94 months), who were diagnosed at our department between 1995 and 2019.Results - VND was unilateral in 17 cases and bilateral in 4 cases. Initial referral diagnoses included suspected primary bone tumor (n = 9), fracture (n = 3), osteomyelitis (n = 2), and metastasis (n = 1). The referral diagnosis was more likely to be VND in asymptomatic than symptomatic patients (4/6 vs. 2/15). More MRI scans were performed in unilateral than bilateral VND (median 2 vs. 0). All 15 symptomatic patients underwent nonoperative treatment and reported a resolution of symptoms and return to physical activity after a median time of 5 months (IQR 0-6).Interpretation - By understanding the physiological course of VND during skeletal maturation, unnecessary diagnostic and therapeutic measures can be avoided and uncertainty and anxiety amongst affected patients, their families, and treating physicians can be minimized.

The efficacy of guided growth as an initial strategy for Blount disease treatment.

PURPOSE: The aim of this study was to evaluate the success of guided growth by temporal hemiepiphysiodesis of the lateral proximal tibia as a first line treatment option for Blount disease. METHODS: This was a retrospective multicentre study conducted in five centres, covering data on 55 limbs in 45 patients, with an average follow-up of 24.5 months following plate insertion. Preoperative alignment analysis was compared with three measurements taken postoperatively. The normalization of the mechanical medial proximal tibia angle (mMPTA) was defined as the primary outcome measure. RESULTS: Mean age at surgery was 9.5 years. Average preoperative mMPTA was 77°. On average, at 24.5 months post-surgery, mMPTA was 86.33°, while 43/55 limbs (78.18%) have achieved normalization (mMPTA 85° to 90°). Average rate of correction was 1° per month. When grouping the children as infantile (11 limbs), juvenile (12 limbs) and adolescent (32 limbs), operated on before the age of four years, between four and ten years and after the age of ten years, respectively, 63.63%, 66.67%, 87.5% have completed correction of deformity during the follow-up period. Interestingly, the femoral component of the deformity has achieved correction as well in 33/55 limbs (64%). CONCLUSION: Hemiepiphysiodesis is an effective first line treatment for Blount disease. Overall success rate is good but varies according to child's age. Adolescent Blount has the best chance of achieving full correction while same treatment is less effective in infantile Blount.Level of evidence: IV.

Leg Length Discrepancy- Treatment Indications and Strategies.

BACKGROUND: Many people have leg-length discrepancies of greater or lesser severity. No evidence-based studies on the need for treatment are currently available. METHODS: This review is based on publications retrieved by a selective search in the PubMed database, as well as on published recommendations from Germany and abroad and on the authors' own clinical experience. RESULTS: If the two legs are of different lengths, this is generally because one leg is too short. It is debated whether leg-length discrepancy causes pain or long-term musculoskeletal disturbances. A direct connection to back pain is questionable, but a mildly elevated incidence of knee arthritis seems likely. The evidence base on the indications for treatment of leg-length discrepancy is poor; only informal consensus recommendations are available. There are a wide variety of conservative and surgical treatment options. The final extent of a leg-length discrepancy first noted during the growing years can be estimated with predictive algorithms to within 2 cm. The treatments that can be considered include a shoe insert, a high shoe, or an orthosis, surgically induced slowing of growth by blockade of the epiphyseal plates around the knee joint, or leg lengthening with osteotomy and subsequent distraction of the bone callus with fully implanted or external apparatus. Changes in leg length exert marked mechanical stress on the soft tissues. If the predicted leg-length discrepancy exceeds 5 cm, initial leg-lengthening treatment can already be considered during the patient's growing years. CONCLUSION: It must be discussed with each patient individually whether the treatment should be conservative or surgical. The extent of the discrepancy is not the sole determining factor for the mode of treatment. The decision to treat is always elective.

A new standard radiographic reference for proximal fibular height in children.

Background and purpose - To date there is a lack of studies defining the anatomical position of the proximal fibula. This is especially relevant when planning surgical interventions affecting the knee joint such as permanent or temporary epiphysiodesis to correct leg length discrepancies or angular deformities in growing patients. The goal of this study is to establish a standardized measurement technique and radiological reference values for the position of the proximal fibula in children.Patients and methods - 500 measurements were performed in calibrated long standing anteroposterior radiographs of 256 skeletally immature patients (8-16 years; 233 female, 267 male legs). As a radiographic reference in the frontal plane, the distance between the center of the proximal tibial growth plate and a line tangential to the tip of the fibular head and horizontal to the imaging plane was measured (dPTFH).Results - The average value of dPTFH in the studied population (median age 12 years) was -2.7 mm (SD 3, CI -3.0 to -2.5) and normally distributed (p = 0.1). There were no clinically significant sex or age-dependent differences. The inter-rater reliability analysis showed excellent ICC values (ICC = 0.88; CI 0.77-0.93).Interpretation - This study provides a new radiographic reference value to assess the position of the proximal fibula in relation to the proximal tibia in children and adolescents. This reference can aid preoperative decision-making as to whether additional fibular epiphysiodesis is necessary when performing tibial epiphysiodesis to correct moderate leg-length discrepancies.

The Joint Angle Tool for Intraoperative Assessment of Coronal Alignment of the Lower Limb.

AIM: Presentation of the joint angle tool (JAT), a low-cost goniometer for intraoperative assessment of the lower limb alignment. BACKGROUND: Intraoperative assessment of coronal alignment is important when performing corrective osteotomies around the knee and ankle, limb lengthening, and trauma surgery. JAT provides surgeons with information about the anatomic and mechanical axes intraoperatively based on true anteroposterior radiographs. TECHNIQUE: JAT consists of pre-printed joint orientation angles of the anatomic and mechanical axis including normal variations on a plastic sheet. It is placed on the screen of the image intensifier after obtaining a true anteroposterior image. The pre-printed joint orientation angles can assist the surgeons intraoperatively in achieving the pre-planned axis correction. Here, its feasibility is demonstrated in four cases. CONCLUSION AND CLINICAL SIGNIFICANCE: JAT is a modified goniometer that allows intraoperative assessment of the mechanical and anatomic axis. JAT is applicable throughout the entire surgical procedure irrespective of the method of internal fixation and may provide additional reassurance of correct alignment. JAT consists of a plastic sheet with printed joint orientation angles and their normal variation. JAT is freely available from profeedback.dk/JAT/JAT.pdf for use and modification according to the Creative Commons license (CC BY-SA 4.0) if this paper is attributed. HOW TO CITE THIS ARTICLE: Abood AA-H, Petruskevicius J, Vogt B, et al. The Joint Angle Tool for Intraoperative Assessment of Coronal Alignment of the Lower Limb. Strategies Trauma Limb Reconstr 2020;15(3):169-173.

Deformity correction and extremity lengthening in the lower leg: comparison of clinical outcomes with two external surgical procedures.

OBJECTIVE: Distraction osteogenesis is a method of stimulating the growth of new bone tissue in order to lengthen the extremities or bridge resected bone defects. In addition to the now-established intramedullary procedures, two different fixator systems are in use. The present study investigated the classical Ilizarov ring fixator (IRF) and a hexapod to assess the precision of lower-leg lengthening and complications classified using the Paley criteria for problems, obstacles, and complications. The study also examined the follow-up results in functional tests to assess outcomes in terms of range of motion in adjacent joints, daily activities, and quality of life. PATIENTS AND METHODS: A total of 43 patients (53 segments) who were treated over a period of 16 years were re-assessed. In 33 segments, treatment was carried out with the hexapod Taylor Spatial Frame (TSF); the conventional IRF was used in 20 segments. The patients' mean age was 13.5 years (range 2-54 years). The follow-up examinations were carried out 2-15 years postoperatively and comprised measurement of a current leg axis view with the patient standing, calculation of a knee score, activity scores, ankle joint scores, and assessment of motor function and sensory function using appropriate scores in the lower leg and foot. The post-treatment health-related quality of life was assessed using the Short-Form Health Survey-36 questionnaire. RESULTS: Using the Paley criteria, far fewer problems occurred in the TSF group in comparison with the IRF (TSF 12.1%, IRF 50%). In the problems category, significant differences were observed with regard to axial deviation (TSF 0%, IRF 36.8%) and pin infections (TSF 9.1%, IRF 40%). Comparison of the obstacles and complications did not identify any significant differences between the two groups. Analysis of the scores for the knee, activity, and motor function/sensory function also did not show any marked discrepancies, apart from a major difference in mobility in the upper and lower ankle joints with poorer findings in the TSF group. CONCLUSIONS: During treatment, the TSF ring fixator leads to fewer problems, fewer secondary axial translations, and fewer pin infections. However, with temporary transfixation of the ankle joints, the TSF system is also associated with postoperative deterioration in mobility in the upper and lower ankle joint.

How precise is the PRECICE compared to the ISKD in intramedullary limb lengthening? Reliability and safety in 26 procedures.

BACKGROUND AND PURPOSE: The PRECICE intramedullary limb lengthening system uses a new technique with a magnetic rod and a motorized external remote controller (ERC) with rotational magnetic field. We evaluated the reliability and safety of the PRECICE system. METHODS: We compared our preliminary results with PRECICE in 24 patients (26 nails) with the known difficulties in the use of mechanical lengthening devices such as the ISKD. We used the Paley classification for evaluation of problems, obstacles, and complications. RESULTS: 2 nails were primarily without function, and 24/26 nails lengthened over the desired distance. Lengthening desired was 38 mm and lengthening obtained was 37 mm. There were 2 nail breakages, 1 in the welding seam and 1 because of a fall that occurred during consolidation. ERC usage was problematic mostly in patients with femoral lengthening. Adjustment of the ERC was necessary in 10 of 24 cases. 15 cases had implant-associated problems, obstacles were seen in 5 cases, and complications were seen in each of 4 cases. INTERPRETAION: The reliability of the PRECICE system is comparable to that of other intramedullary lengthening devices such as the ISKD. The motorized external remote controller and its application by the patients is a weak point of the system and needs strict supervision.

Publication rate of abstracts presented at European Paediatric Orthopaedic Society Annual Meetings, 2006 to 2008.

BACKGROUND: The quality of the abstracts presented at a conference reflects the scientific work and level of activity of the scientific association concerned. The aim of the present study was to determine the rate of publications of podium presentations and posters at the conferences of the European Paediatric Orthopaedic Society (EPOS) from 2006 to 2008 and to identify factors that favor publication in peer-reviewed journals. The results are compared with those of other international societies. METHODS: All 646 abstracts (including podiums, posters, and e-posters) presented at the EPOS conferences were investigated using the PubMed database to identify any corresponding published articles in the journals listed in the database. A period of 5 years before and after the relevant conference was used for the PubMed search. Factors influencing publication and the quality of the study, such as the type of presentation and the level of evidence, were also investigated. RESULTS: A publication rate of 36.7% was observed, corresponding to 237 publications of 646 abstracts. The period to publication showed a mean of 13.88 ± 1.34 months. It was found that abstracts of podium presentations were published significantly more often than poster abstracts (P<0.001). Experimental studies, with a publication rate of 50.9%, showed better results than clinical studies (36.0%). Overall, the articles were published in 61 different journals, with the largest number (n=50) appearing in the Journal of Pediatric Orthopaedics. In addition, the present study shows that abstracts with a higher level of evidence were associated with a higher publication rate. CONCLUSIONS: At 36.7%, the rate of publication of EPOS abstracts is within the range reached by other specialist orthopaedics societies, such as the German Society of Orthopaedics and Trauma Surgery (36%) and the British Orthopaedic Association (36%). However, it is lower than the publication rate of the Pediatric Orthopaedic Society of North America (POSNA), at 50%. The high percentage of unpublished conference abstracts (63%), which did not go through a peer-reviewed process, casts doubts upon the practice of utilizing the citation of abstracts based purely on conference abstracts. LEVEL OF EVIDENCE: Statistical study.

Prophylactic titanium elastic nailing (TEN) following femoral lengthening (Lengthening then rodding) with one or two nails reduces the risk for secondary interventions after regenerate fractures: a cohort study in monolateral vs. bilateral lengthening procedures.

BACKGROUND: Femoral fracture rates of up to 30% have been reported following lengthening procedures using fixators. "Lengthening then rodding" uses one or two titanium elastic nails (TENs) for prophylactic intramedullary nailing to reduce this complication. The aim of the study was to decide if usage of only one TEN is safe or has it a higher risk of getting a fracture? And we asked if there is a difference between patients with monolateral or bilateral lengthening procedures according to their fracture rate? METHODS: One or two TENs were implanted in two groups of patients (monolateral and bilateral) after femoral lengthening procedures. The regenerate quality was classified using the Li system and fractures were categorized using the Simpson and Kenwright classification. The follow-up period was at least 1 year after removal of the frame. RESULTS: Sixty-seven patients with 101 femoral lengthening procedures were included in 2007-2011. Group A included 34 patients with bilateral lengthening due to congenital short stature. Group B consisted of 33 patients with congenital disorders with leg length discrepancies. Seven fractures in six patients were seen in group A and five fractures in group B. One patient had residual shortening of 1 cm, and 11 fractures healed without relevant deviation (< 5°) or shortening (< 5 mm). A soft-tissue infection in one patient led to early removal of one TEN. CONCLUSIONS: Fractures occurred in both groups of patients in total in 12 of the 101 cases (12%). The rate of secondary interventions was markedly reduced. Usage of one or two TENs did not influence the fracture rate.

Lower limb lengthening in patients with disproportionate short stature with achondroplasia: a systematic review of the last 20 years.

Parents of children suffering from disproportionate short stature due to achondroplasia may wish to have surgical leg lengthening carried out for the child. The aim is not to increase height, but rather to achieve physiological proportions in the body. In a systematic review of the literature on the topic dating from the last 20 years, the surgical approaches used for this purpose were analyzed in accordance with the Preferred reporting items for systematic reviews and meta-analyses (PRISMA) criteria. Twelve studies show that to date, involvement of the child in decision-making at the start of treatment has been expected and that it is recommended from the age of 12. In highly heterogeneous patient groups, with varying factors involved and different techniques being used, lengthening (often by more than 10 cm) is described. High complication rates are reported, with many setbacks often requiring repeat surgery. Using PALEY'S multiplier method, the expected standing height, sitting height, and leg length can be predicted and an individualized treatment approach can be planned and operative procedures could be started in early childhood as PERETTI suggests. As the patients are unable to be involved in decision-making as young children, these data may provide a basis for offering differentiated advice to parents, who usually consult a pediatric orthopedist at a very early stage in the child's life.

Proximal fibula resection in the treatment of bone tumours.

BACKGROUND AND OBJECTIVES: We present a large study of patients with proximal fibula resection. Moreover we describe a new classification system for tumour resection of the proximal fibula independent of the tumour differentiation. METHODS: In 57 patients the functional and clinical outcomes were evaluated. The follow-up ranged between six months and 22.2 years (median 7.2 years). The indication for surgery was benign tumours in ten cases and malignant tumours in 47 cases. In 13 of 45 patients, where a resection of the lateral ligament complex was done, knee instability occurred. In 32 patients a resection of the peroneal nerve with resulting peroneal palsy was necessary. RESULTS: Patients with peroneal resection had significantly worse functional outcome than patients without peroneal resection. An ankle foot orthosis was tolerated well by these patients. Three of four patients with pathological tibia fracture had local radiation therapy. There was no higher risk of tibia fracture in patients with partial tibial resection. CONCLUSIONS: Resection of tumours in the proximal fibula can cause knee instability, peroneal palsy and in cases of local radiation therapy, a higher risk of delayed wound healing and fracture. Despite the risks of proximal fibula resection, good functional results can be achieved.

The postoperative patella height: a comparison of additive and subtractive high tibial osteotomy in correcting the genu varum.

INTRODUCTION: Intraligamentary correctional operations like a high tibial osteotomy were performed in genua valga to prevent later medial gonarthrosis especially in younger patients. An unwanted effect of this method seems to be the inferiorization of the patella. This is feared because of the complications in case of subsequent alloarthroplasty. Besides the classical Coventry method as a subtractive osteotomy the hemicallotasis has been established as a sustainable additive procedure. This means a gradual open wedge correction using an external fixateur. OBJECTIVE: The aim of this study was to determine the position of the patella pre- and postoperatively and in follow-ups with subtractive versus additive intraligamentary high tibial osteotomies on the basis of five radiological parameters. It was expected that an additive osteotomy leads to an inferiorized patella position whereas a subtractive osteotomy leads postoperative to a higher position of the tibia. METHOD: Between 1990 and 2001, 54 patients (61 legs) had undergone an operation due to a genu varum either by the subtractive osteotomy (n = 30) according to Coventry's method or the additive gradually hemicallotasis (n = 31) with an external fixator. RESULTS: In coherence with the Coventry's osteotomy a significant inferiorization of the postoperative patella position with all five radiological parameters was observed, the hemicallotasis showed no operation-related significant alteration of the patella height. Instancing the Insall-Salvati Index there were four (12.9%) preoperative and three (9.7%) postoperative patella baja positions detected. Along with the subtractive osteotomy there were 5 preoperative patellae baja (16.7%) and 11 postoperative patellae baja (36.7%) positions. Furthermore a significant interrelation was noticed between the extent of the correctional angle and the postoperative alteration of the patella. CONCLUSION: The results are surprising, contrary was expected. First this can be explained by its gradual, additive correctional property in contrast to the spontaneous correction by the conventional method according to Coventry, second by the postoperative treatment, which allows an early mobilization and active remedial gymnastics, provided an impact resistant osteosynthesis by a fixateur externe is given. In the case of the additive hemicallotasis an intraligamentary osteotomy is recommended. Technically expensive step cuts in order to osteotomize below the tuberositas tibiae are not necessary. Due to the low quota of complications and the small operative expense the continuous distraction is preferential to ad hoc correction. A postoperative patella baja position has not to be afraid in hemicallotasis.

Estimation of patient dose and associated radiogenic risks from limb lengthening.

UNLABELLED: Limb-lengthening procedures include a series of radiographic examinations to follow the lengthening process and callus formation. We quantified ionizing radiation exposure during lengthening treatment and estimated the risks associated with this exposure in 53 patients undergoing lengthening procedures. Field size and tube voltage of all radiographs and fluoroscopy time during surgery were recorded. According to conversion factor tables of organ doses, the cumulative organ dose was estimated. Location of lengthening, age, complications during lengthening procedure, range of lengthening, healing index, and other factors affecting the duration of the lengthening procedures were analyzed. Average lengthening was 4.8 cm (range, 3.0-12.5 cm). The average cumulative organ dose for a straight lengthening procedure was 3.1 mSv (range, 0.2-12.5 mSv). The average organ dose per centimeter of lengthening was 0.7 mSv/cm (range, 0.03-5.9 mSv/cm). Doses for patients with tibial lengthening (0.3 mSv/cm) were less than doses for patients with femoral lengthening (1.1 mSv/cm). Age, complications, range of lengthening, and healing index did not influence the dosage of radiation per centimeter lengthening. We judge the average patient's exposure during a limb-lengthening procedure as tolerable, but femur lengthening results in a higher cumulative organ dose. LEVEL OF EVIDENCE: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Correction of leg-length discrepancy after hip transposition.

Four patients were treated with limb lengthening to correct a leg-length discrepancy that developed after a hip transposition after pelvic resection for sacroma of the pelvis. Three patients had Ewing's sacroma and one patient had osteosarcoma. All patients received chemotherapy; radiotherapy also was administered to the three patients with Ewing's sacroma. Femur lengthening was started at an average of 5.7 years (range, 4.4-6.8 years) after tumor surgery. At the start of elongation, the average age of the patients was 17.3 years (range, 10.3-20.8 years). The average leg-length discrepancy was 10.3 cm (range, 6-12 cm). The average of achieved lengthening was 6.4 cm (range 6-7.5 cm). The average healing index was 32 days (range, 27-40 days) per 1-cm elongation. According to the classification of Paley, two problems and two minor complications were treated by additional interventions. At the final followup, the average functional score was 22 (73%) according to the system of the Musculoskeletal Tumor Society. Leg-length discrepancy after hip transposition can be corrected with distraction osteogenesis. All patients who wore a stiff ankle-foot orthosis before lengthening wore an ordinary shoe lift after lengthening. The problems of the lengthening procedure are similar to the general complication rate of bone lengthening. Because the 5-year survival after resection of a pelvic sarcoma is only 20% to 30%, leg lengthening after hip transposition should be offered only to long-term survivors with at least 5 years event-free survival.