Extracorporal noninvasive acute retraction of STRYDE® for continued lengthening in cases with limited nail stroke: a technical less invasive solution to reload the STRYDE®.

With STRYDE® nails (NuVasive Specialized Orthopedics, San Diego, CA), lengthening nails for full weight-bearing during callus distraction have been available CE-certified since February 2019 in Europe. At present only antegrade femur nails and tibia nails with various lengths and diameters are available. Due to a mismatch of bone length and realizable (implantable) nail length e.g., in cases of skeletal dysplasia or achondroplastic dwarfism, it may happen that a desired lengthening of 6-8 cm cannot be realized because of a nail stroke from only 5 cm. Retrograde usage of antegrade piriformis nails is technically possible as an individual (off label use) procedure since so far no retrograde implants are available. A new method of surgical intervention for retraction of the STRYDE nails at the end of the nail stroke with ongoing callus distraction in patients with bilateral femoral extension under anesthesia with extracorporeal use of the fast distractor device is described in detail. It is safe and with low risk for a reload of a capacity of 3-4 cm for antegrade and retrograde femoral implantation situation for the patient. The acute reload of the STRYDE nail stroke for further distraction is possible without skin incision or invasive soft tissue approaches. Application of the fast distractor extracorporeal within a few minutes is described in detail. The intervention is technically reproducible and can be performed for the proximal femur with antegrade STRYDE nails as well as for the distal femur with retrograde STRYDE nails in adult patients.

Evaluation of the SMALL nail: Drive technology and behavior in situ.

Although clear advances have been made during the last 5 years, practical difficulties persist for patients and surgeons in procedures for intramedullary lengthening of long bones. In particular, precise adjustment of the desired amount of lengthening and technically reliable checking of the length actually achieved are problematic. An intramedullary nail with a new type of drive that exploits the shape memory effect has been constructed. The drive technology and the behavior of the intramedullary nail in situ were evaluated in a cadaver experiment. Three shape memory alloy limb lengthening (SMALL) nails were implanted in a body donor. The SMALL nail contains a spring coupled to a shape memory element consisting of a nickel-titanium alloy. This shape memory element "remembers" its initial state before the lengthening through the spring and can return to it when it is warmed. A cartridge heater inside the lengthening nail is warmed using transcutaneous induction with high-frequency energy via a subcutaneously implanted coil. For evaluation, two SMALL nails were implanted into the femora (antegrade on the left and retrograde on the right) and one SMALL nail was implanted into the left tibia. Lengthening by 50mm was attempted using repeated activation of the drive mechanism. At the same time, test parameters for temperature increases and cooling periods were continually monitored and the data were subsequently analyzed. The nail's mechanism worked in principle, but was inadequate in view of success rates (number of lengthening steps attempted versus number of lengthening steps achieved) of 21% for the SMALL nail in the tibia and left femur and 14% for the nail in the right femur. The temperature values measured during the distraction experiments show that high-frequency energy induction in the SMALL nail gives no cause for concern for patients.

[Guided growth in children and adolescents. Correction of leg length discrepancies and leg axis deformities]. / Wachstumslenkung bei Kindern und Jugendlichen. Korrektur von Beinlängendifferenzen und Beinachsendeformitäten.

The treatment of crooked legs and unequal leg length is one of the key tasks of orthopedic surgery. While mature patients usually require complex and invasive surgical interventions, the growth potential of the physes can be used to advantage for correction of these leg length discrepancies and axis deformities of the legs in growing children and adolescents. This guided growth is induced by temporary or permanent and partial or complete arrest of the growth plate, depending on the indications. This technique is called epiphysiodesis. Although these procedures are principally less invasive with few complications, accurate preoperative indications and planning, precise surgical techniques and careful postoperative follow-up examinations are mandatory prerequisites to achieve the desired therapeutic target.

[Spectrum of indications for intramedullary or external fixators for axis correction and limb lengthening]. / Indikationsspektrum intramedullärer oder fixateurgebundener Achskorrekturen und Extremitätenverlängerungen.

Corrective osteotomy is a well established operative option for correction of predominantly congenital skeletal deformities on the growing skeleton. The indications for the use of a suitable corrective instrument result partly from the location, severity of the deformity and the presence of concomitant leg length discrepancies. External fixators are predominantly used for correction of combined deformities. For isolated leg length differences limb lengthening nails can be implanted but only after growth plates have become closed; however, only a few combined deformities can be addressed in this way. Often several surgical steps are necessary. A careful treatment plan can only be created if the analysis of the deformity is carried out with appropriate parameters and a correct prognosis of the further development. The aim of this paper is to describe the indications for the corrective instruments, the planning of corrections and the presentation of typical indications for axis correction and limb lengthening.

[Determination of skeletal age : comparison of the methods of Greulich and Pyle and Tanner and Whitehouse]. / Bestimmung des Skelettalters : Vergleich der Methoden nach Greulich und Pyle sowie Tanner und Whitehouse.

PURPOSE: The main purpose of this study was to evaluate the accuracy and the time required to determine skeletal age (SA) in healthy children by the methods of Greulich and Pyle (GP) and of Tanner and Whitehouse (TW). Based on these results recommendations for routine clinical practice is to be established. MATERIALS AND METHODS: In this study a total of 63 children between the ages of 5 and 18 years were included. Each conventional radiographic image of the left hand was assessed under blinded conditions by 5 or 6 examiners and the time needed was recorded. The assessments were repeated after 2 months. RESULTS: The average chronological age was estimated slightly too low by the GP method and clearly too high by TW. The mean deviation between the results of two examiners tended to be higher with the TW method than with GP. Repeated assessments of SA by the same examiner deviated only slightly for both methods. The time taken to assess the SA by GP was less than half as long as for TW. An improvement in accuracy of SA estimation after repeated use was only observed for GP. CONCLUSION: Of the two methods tested neither proved to be superior. Determination of SA by the GP method was found to be more suitable for routine clinical practice.

Walking ability of children with a hexapod external ring fixator (TSF®) and foot plate mounting at the lower leg.

Wearing an external fixator for several months can be expected to profoundly affect the ability to walk, but, in principle, full weight-bearing is possible during corrective procedures with the Taylor Spatial Frame (TSF). The present prospective cohort study was conducted to assess whether patients are able to walk with or without crutches during treatment with a TSF on the lower leg. Twenty-four patients (10 girls, 14 boys; average age 11 years, range 6-17) scheduled for fixator surgery with osteotomies in the lower leg and foot mounting were included. Dynamic foot loading during free walking was measured with plantar pressure measurements. The contact area, contact time and contact pressure on the foot plate were recorded and normalized to body weight. In the first postoperative week, all patients needed crutches and 67% showed partial weight-bearing. At the second measurement, about 6 weeks after surgery, 21% of the patients could walk without crutches and 58% were partially weight-bearing with crutches. On the day before fixator removal, 50% of the patients were fully weight-bearing without crutches and 38% were partially weight-bearing, but 12% could not bear any weight or were unable to walk. When a ring fixator is used to correct lower leg deformity and prevent equinus, there is minimal risk of complete dependence and abasia. This study shows that up to 88% of the pediatric patients are able to walk while wearing the fixator. Already a few days after surgery, two-thirds of the patients were partially weight-bearing with crutches, and only 12% needed a wheelchair and were not able to walk with the fixator.

Intramedullary limb lengthening with the Intramedullary Skeletal Kinetic Distractor in the lower limb.

We report the results of intramedullary leg lengthening conducted between 2002 and 2009 using the Intramedullary Skeletal Kinetic Distractor in 69 unilateral lengthenings involving 58 femora and 11 tibiae. We identified difficulties that occurred during the treatment and assessed whether they were specifically due to the implant or independent of it. Paley's classification for evaluating problems, obstacles and complications with external fixators was adopted, and implant-specific difficulties were continuously noted. There were seven failures requiring premature removal of the device, in four due to nail breakage and three for other reasons, and five unsuccessful outcomes after completion of the lengthening. In all, 116 difficulties were noted in 45 patients, with only 24 having problem-free courses. In addition to the difficulties arising from the use of external fixators, there were almost the same number again of implant-specific difficulties. Nevertheless, successful femoral lengthening was achieved in 52 of the 58 patients (90%). However, successful tibial lengthening was only achieved in five of 11 patients (45%).

[Dieterich's Disease--the rare aseptic necrosis of the metacarpal head]. / Morbus Dieterich--die seltene aseptische Knochennekrose der Metakarpaleköpfe.

The rare diagnosis of the Dieterich's disease at the head of the metacarpal III is presented on the case of a 19-year-old female patient. While aseptic bone necroses at the hand skeleton in handsurgical special departments are not rare and diagnostics and choice of the right treatment are not difficult, there are quite rare findings, which are not commonly known. Dieterich's disease finds precipitation in the literature in a handful of articles, mostly case reports. Dieterich saw among 8 patients 7 women, with a distribution of 7 concerned metacarpal bone III and one metacarpal bone IV. A preference of the female sex or the metacarpal bone III cannot be derived from it. Aseptic necroses at the hand are rarer than at the foot skeleton. Clinically, a swelling at the extensor side of the finger basic joint can exist with movement restriction, occasionally is the hand over it slightly turned red. Mechanical load aggravates the complaints. The clinical aspect, X-ray and therapy options are differentially presented and discussed with consideration of the specific literature.

[Not "only" a dislocation of the hip: functional late outcome femoral head fractures]. / Wenn die Hüfte nicht "nur" luxiert: Funktionelle Spätergebnisse nach Hüftkopffrakturen.

BACKGROUND: Traumatic hip dislocation combined with fracture of the femoral head is a rare condition for which little known in terms of long-term prognosis. The aim of the retrospective study presented here was to evaluate the clinical and radiological outcome of this specific injury. PATIENTS AND METHODS: In a 23 year period, 18 patients (17 male) with an average age of 25.6 (range 15-55 years) were treated. There were four type-I, three type-II, no type-III, and 11 type-IV fractures according to the Pipkin classification (1957). RESULTS: The average time to sufficient reduction was 136 min (60-420 min), two by open means. A total of 16 patients were operated for open reduction and internal fragment fixation, 13 through a dorsal approach. All patients filled out a standardized questionnaire, and clinical and radiological examinations were also carried out on average 12.6 years (range 59-247 months) after injury. Four scoring systems were used to classify the outcome: Thompson and Epstein (1951): very good = 1, good = 10, fair = 4, poor = 3; Merle D'Aubigne (1954): very good = 9, good = 5, fair = 0, poor = 4; Harris (1969): Pipkin I = 81 points, Pipkin II = 97 points, Pipkin IV = 73 points (mean); Brooker (1973): grade I = 5, grade II = 1, grade IV = 2. CONCLUSION: Quality of life was not reduced in most patients in the long term, however three of four patients suffering Pipkin type-IV fractures developed functional restrictions with poor results. We conclude that acute reduction of the dislocated joint and anatomical reconstruction of the femoral head instead of primary hip replacement may end in good to excellent results in type-I and type-II fractures. Due to the young age of these patients, joint reconstruction should always be the first choice even in type-IV fractures with a higher probability of poor prognosis.