Innovative Hip Distraction Approaches for Total Hip Arthroplasty in Crowe IV Developmental Dysplasia or Similar High-Riding Patients.

BACKGROUND: Total hip arthroplasty (THA) for dislocated hips (Crowe IV dysplasia) presents unique challenges. Conventional approaches involve subtrochanteric osteotomies, but are complex with additional fixation and potentially lead to limb length discrepancies, nerve palsies, and other complications. An alternative strategy is a staged approach, where the femoral head (or remnant) is gradually lowered (distraction technique) to align with the true acetabulum over a period of time, followed by a second-stage anatomically acetabular-positioned THA. External fixation distraction and telescoping internal lengthening devices have been utilized to achieve preoperative alignment. We evaluated these techniques, including the types, time, and amount of distraction needed, as well as outcomes and complication rates. METHODS: In this retrospective case series, 14 patients (9 women, 5 men), who had a mean age of 32 years (range, 16 to 67), underwent staged surgical interventions using hip distraction using external fixators or internal lengthening devices for hip dysplasia and other pathologies (Perthes disease, osteonecrosis) in preparation for a second-stage anatomically placed THA. The mean follow-up duration for external-fixation patients was 10 years (range, 6.5 to 13.4). RESULTS: Staged treatment involved external fixators (n = 8) or internal lengthening devices (n = 6) with a device placement mean of 48 days (range, 42 to 71). The amount of distraction ranged from 6 to 12 cm. There were 2 patients who required uncomplicated revision of the internal lengthening devices, and another patient had a temporary peroneal nerve palsy. There was 1 patient who underwent an acetabular revision at 7 years. CONCLUSIONS: We focused on a challenging patient cohort that emphasizes the efficacy of staged interventions in managing Crowe Type IV dysplasia and similar cases. Favorable outcomes were found with the immediate transition to THA after device removal that effectively addressed soft-tissue contractures and femoral migration. Despite the need for further validation via larger, prospective studies, this innovative approach may pave the way toward optimizing this strategy for these difficult hip pathologies.

Femoral head reduction osteotomy for the treatment of late sequela of Legg-Calvé-Perthes disease and Perthes-like femoral head deformities.

Femoral head reduction osteotomy (FHRO) was described to treat misshapen femoral head that is causing intraarticular hip pain. The published literature showed discrepancies in patient selection, surgical techniques, and decision to perform concurrent acetabular osteotomy. Very few studies used Standardized Outcome Measures (SOMs). This study aims to describe the technique of FHRO and report the results of our series of 22 patients using SOMs and compare them to former peer-reviewed articles. Twenty-two hips in 22 patients with hip pain caused by mishshapen femoral were treated with FHRO with or without triple pelvic osteotomy (TPO). Patients with poor hip range of motion and significant hip joint arthritis were excluded. The mean patient age was 15.8 (range, 9.2-23.9). Clinical results were reported using the HHS. Radiographical results were reported by comparing Lateral Center Edge Angle (LCEA), extrusion index, Tonnis angle, head size percent, sphericity index, and distance from tip of trochanter to center of femoral head. The mean follow-up was 3.2 years. Only 5 patients received TPO. The HHS showed statistical improvement from 62.0 to 81.6 (The median interquartile range 63.5-88.5). Five patients had HHS less than 70 at the latest follow up. All radiographic parameters except the Tonnis angle, showed statistically significant improvement. FHRO with or without pelvic osteotomy is a good salvage procedure for patients presenting with misshapen femoral head with intraarticular hip pain, who still have good preoperative ROM with no signs of hip arthritis. Level of evidence: IV.

Biopsy Proven Focal Osteolysis in a Stainless-Steel Limb-Lengthening Device: A Report of Three Cases.

Three pediatric patients presented with histologically confirmed osteolysis after limb lengthening with a magnetic, telescoping, stainless-steel device. The first patient's findings were discovered radiographically before routine removal of the device. In all cases, intraoperative histologic specimens taken from around the modular junction demonstrated particle-laden macrophages with suspicion for metal debris. Silicone debris was also identified. We found definitive osteolysis secondary to metal at the modular junction of three stainless-steel lengthening implants. This process is not well-understood in the setting of limb lengthening and should be examined further.

Simultaneous Bilateral Femoral and Tibial Lengthening in Achondroplasia.

Previous studies on lengthening for achondroplasia have reported bilateral extensive femoral lengthening followed by bilateral extensive tibial lengthening. To decrease trauma on soft tissues and joints, we propose bilateral simultaneous moderate femoral lengthening and moderate tibial lengthening followed by a similar repeat lengthening a few years later. Fifty patients with achondroplasia underwent 65 simultaneous bilateral femoral and tibial lengthening procedures. Segment lengthening amount and adverse events were obtained from medical records. Mean follow-up after bone healing was 35.6 months. Mean tibial lengthening was 52 mm; mean femoral lengthening was 72 mm. Average healing index was 1.4 months/cm for the tibia and 1 month/cm for the femur. Mean duration of treatment with external fixation was 6.7 months (range, 4.4-10.5 months). Thirty-eight (76%) of 50 patients experienced one or more adverse events during lengthening. We observed 78 adverse events, 35 (45%) of which required additional surgical procedures. All resolved by the end of treatment. Mechanical axis deviation improved from a mean of 15 mm medially to 8 mm medially. Simultaneous lengthening of four segments in patients with achondroplasia is a feasible strategy. Compared with isolated femoral or tibial lengthening, distributing the lengthening between the femur and tibia decreases total external fixator time.

Lengthening With Monolateral External Fixation Versus Magnetically Motorized Intramedullary Nail in Congenital Femoral Deficiency.

BACKGROUND: Limb lengthening for congenital femoral deficiency (CFD) with or without fibular hemimelia can be performed with both external and internal devices. The purpose of this study is to compare clinical outcomes of femoral lengthening utilizing monolateral external fixation versus a magnetically motorized intramedullary nail in patients with CFD with or without fibular hemimelia. METHODS: This retrospective review included 62 patients with femoral lengthening, 32 patients had monolateral external fixation (group A), 30 patients had internal lengthening nail (group B). Mean age in years was 9.4±3.8 and 15.4±4.9 for groups A and B, respectively. Mean follow-up in years was 4.47±2.7 and 1.86±0.7 years for groups A and B, respectively. RESULTS: Mean lengthening achieved was 5.6±1.7 and 4.8±1.4 cm for group A and group B, respectively (P=0.052). Mean distraction index was 0.7±0.2 mm/d for group A and 0.7±0.2 mm/d for the group B (P=0.99). Mean consolidation index for group A was 29.3±12.7 and 34.8±11.2 d/cm for group B (P=0.08). Mean arc of motion before surgery and at final follow-up were similar between groups (P=0.35). Group A had significantly less range of motion at the end of distraction (P=0.0007) and at consolidation (P<0.0001). Both groups had similar rates of obstacles and complications. A significant difference between groups was found in the total problems (P<0.001) specifically with pin site/superficial infection (P<0.0001). CONCLUSIONS: The intramedullary nail had superior range of motion during the lengthening phase and at consolidation and an overall lower problem complication rate, while maintaining similar distraction and healing indices to monolateral external fixation. Internal lengthening nails represent a significant advance in technology for CFD lengthening. LEVEL OF EVIDENCE: Level IV-therapeutic.

Bone Ninja Mobile App for Reverse Planning Method in Internal Limb Deformity and Lengthening Surgery.

AIM: To report whether Bone Ninja (BN) is a reliable tool to teach the reverse planning method (RPM) for implantable intramedullary (IM) limb-lengthening devices and for deformity correction surgery. BACKGROUND: Motorised fully implantable implantable intramedullary (IM) lengthening devices have been gaining popularity all over the world for limb-lengthening procedures. Multiple advantages have been demonstrated over external fixator-controlled lengthening. Mechanical axis deviation may result if careful preoperative planning and surgical intervention are not completed for femur cases. The RPM proposed by Baumgart has been shown to be an accurate means of arriving at the desired end point. The RPM addresses the ideal correction position accounting for length, angulation, and translation created during lengthening along the nail axis. The original description calls for the use of life-size paper tracings of the bone and large light boxes to allow planning. We propose an alternative method using a digital tool that is readily available. The BN mobile app was developed for patient/physician education and is available for the Apple iPad platform. Bone Ninja has been shown to have similar accuracy for measurements of the limb length and deformity angles when compared to the gold standard picture archiving and communication systems (PACSs). TECHNIQUE: We used BN (version 4.2) on an iPad mini to perform the same RPM steps, using the same terminology originally described by Baumgart. CONCLUSION: Bone Ninja is a simple validated deformity correction tool with accuracy comparable to PACS. It is a reasonable alternative to paper/pencil cutouts for applying RPM for IM limb lengthening and deformity correction surgery. CLINICAL SIGNIFICANCE: We proposed a digitised RPM for internal limb-lengthening surgeries, which is highly feasible and practical to use conveniently without the need for the traditional tedious paper-cutting procedure and related equipment. HOW TO CITE THIS ARTICLE: Hung AL-H, McClure PK, Franzone JM, et al. Bone Ninja Mobile App for Reverse Planning Method in Internal Limb Deformity and Lengthening Surgery. Strategies Trauma Limb Reconstr 2019;14(2):72-76.

Humeral Lengthening with the PRECICE Magnetic Lengthening Nail.

BACKGROUND: Different types of external fixators have been used for humeral lengthening with successful outcomes reported in literature. Motorized intramedullary (IM) lengthening nails have been developed as an alternative to external fixators for long bone lengthening in the lower extremity. QUESTIONS/PURPOSES: This case series reports on using the new technology of IM lengthening nails for humeral lengthening. We assessed the radiological healing and functional outcomes after using the PRECICE IM nail for humeral lengthening. METHODS: This multicenter retrospective study included a total of six humeri in five patients (mean age was 20 years) that underwent lengthening with the magnetic IM PRECICE nail in two centers in the USA. The etiology was humeral growth arrest post-bone cyst (two segments), post-septic growth arrest (two segments), and multiple hereditary exostosis (bilateral segments in one patient). The outcomes measured were the length achieved, distraction index (DI; the length achieved in mm divided by the duration of lengthening in days), consolidation index (CI; number of days from surgery until consolidation divided by the length of the regenerate in cm), complications encountered, and functional outcomes (shoulder and elbow range of motion, the upper extremity functional index (UEFI), and QuickDASH functional scores). RESULTS: The mean follow-up period was 1.8 years (0.9 to 2.4 years). All segments achieved the goal of lengthening; the mean was 5.1 cm (4.5 to 5.8 cm). Mean DI was 0.7 mm/day (0.5 to 0.8). Mean CI was 36 days/cm (25 to 45 days/cm). No complications were observed. At the last follow-up, all patients maintained their preoperative range of motion (ROM) except one patient had reduced shoulder ROM. QuickDASH score and upper extremity functional index showed postoperative improvement compared to the preoperative scores. CONCLUSION: IM lengthening nails can provide successful and safe humeral lengthening. Specifically, the PRECICE nail has accurate control over the lengthening process.

Trochanteric Entry for Femoral Lengthening Nails in Children: Is It Safe?

BACKGROUND: Antegrade intramedullary (IM) nailing for skeletally immature femur fractures can damage the capital femoral epiphysis blood supply, leading to avascular necrosis (AVN) of the femoral head. Reported AVN rates are 2% for piriformis entry and 1.4% for trochanteric entry. None of previous reports described IM lengthening nails for limb lengthening procedures. We have used self-lengthening telescopic nails with a proximal Herzog bend and standard trochanteric entry for femoral lengthening in children. The purpose of this study is to determine whether trochanteric entry IM lengthening nails can be used safely (no AVN or proximal femoral deformity) in the skeletally immature femur. METHODS: A retrospective review was performed between 2004 and 2014 to determine all skeletally immature patients younger than 18 years of age who had a reamed IM lengthening nail inserted through the greater trochanter, with at least 1-year follow-up. RESULTS: Thirty-one femurs were lengthened in 28 patients (17 males and 11 females). The etiology was congenital femoral deficiency (10), achondroplasia (6), post-traumatic (5), hemihypertrophy (3), Ollier disease (2), and miscellaneous (5). An attending surgeon was present for all procedures. Mean age at time of surgery was 12.9 years (range, 7 to 17 y). Mean follow-up was 3.5 years (range, 1.4 to 9 y). The average amount of lengthening was 5.4 cm (range, 3 to 6.7 cm). Twenty-four nails were 10.7 mm in diameter. Seven nails were 12.5 mm in diameter. Intramedullary skeletal kinetic distractor was used in 18 femurs and PRECICE in 13 femurs. Ten segments (7 intramedullary skeletal kinetic distractor; 3 PRECICE) experienced 13 complications. None of the patients developed AVN or proximal femoral deformity. CONCLUSIONS: IM lengthening nails inserted through the greater trochanter may be utilized in skeletally immature patients without increased risk of AVN of the femoral head or proximal femoral deformity. Larger trials would be helpful to confirm our hypothesis. We recommend careful surgical technique with liberal use of the image intensifier to avoid trauma to the femoral head blood supply. LEVEL OF EVIDENCE: Level IV-therapeutic.

Treatment of Post-Traumatic Femoral Discrepancy With PRECICE Magnetic-Powered Intramedullary Lengthening Nails.

OBJECTIVE: To evaluate the outcomes of lengthening post-traumatic femoral segments using a recently available magnetic intramedullary (IM) lengthening system. DESIGN: Retrospective cohort study. SETTING: Urban level II Trauma Center. PATIENTS/PARTICIPANTS: Patients treated for post-traumatic femoral shortening at our institution between 2012 and 2015. We identified 17 femurs lengthened (14 men and 3 women). The mean age was 30 years (range, 11-72 years). INTERVENTION: Magnetic IM lengthening system. MAIN OUTCOME MEASUREMENTS: Amount of lengthening achieved, consolidation index, and complications encountered. RESULTS: The mean follow-up was 2.2 years (range, 1-3.7 years). Sixteen patients achieved the planned lengthening, a mean of 3.8 cm (range, 2.3-6.0 cm). Regenerate consolidation occurred at a mean of 119 days (range, 57-209 days). The mean consolidation index was 32 d/cm (range, 16-51 d/cm). Three patients (18%) experienced complications. CONCLUSION: IM lengthening nails are an improvement over external fixators for treatment of post-traumatic femoral shortening. Within certain limits, their use can be extended to problems of limb-length discrepancy with angular/rotational deformity. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Prophylactic Intramedullary Rodding Following Femoral Lengthening in Congenital Deficiency of the Femur.

INTRODUCTION: Femoral fracture after lengthening of congenital femoral deficiency (CFD) is a common complication with a high incidence, up to 50%. The purpose of this study is to determine whether prophylactic intramedullary Rush rodding after lengthening for CFD is an effective method to prevent femoral fracture and to assess any complications that may result. METHODS: Forty-five femoral lengthenings (43 CFD patients) were performed using external fixation. At the time of frame removal (except for 3 cases, 8 d later), prophylactic intramedullary Rush rods were inserted. Special reaming techniques were developed to pass a Rush rod through the solid regenerate bone and past sclerotic pin sites. Mean age at time of rodding was 6.9 years (range, 2.9 to 14.2 y). Mean duration of treatment with external fixation was 184 days (range, 146 to 461 d). Mean follow-up was 4.2 years (range, 1.3 to 8.2 y). This group of cases was compared with a historical cohort of 95 femoral lengthening procedures for CFD without prophylactic intramedullary rodding after frame removal previously performed at the same institute by the same surgeons. RESULTS: Eight cases (18%) developed fracture despite intramedullary rodding (1 case with relatively high-energy trauma, 3 cases during physical therapy, and 4 cases spontaneously). Only 4 of these fractures required intervention. Fractures were more common when a 3.18 mm Rush rod was used (28%) compared with 4.76 mm (8.3%). Patients with prophylactic rodding had a significantly lower incidence of femur fracture rodding than those who did not (18% vs. 34%, respectively; P=0.04). Three out of 45 Rush rods (7%) developed infection that were treated by debridement and removal of the rod, and all healed uneventfully without residual or recurrent infection. There were no cases of avascular necrosis. CONCLUSIONS: Prophylactic intramedullary rodding is a safe and effective method to prevent femoral fractures after CFD lengthening. Use of 4.76 mm rod is preferred. The risk of infection is acceptable, when compared with the risk of fracture, loss of length, and angulation. LEVEL OF EVIDENCE: Level III-a retrospective comparative study.

Evaluation of a Mobile Application for Multiplier Method Growth and Epiphysiodesis Timing Predictions.

BACKGROUND: The multiplier method (MM) is frequently used to predict limb-length discrepancy and timing of epiphysiodesis. The traditional MM uses complex formulae and requires a calculator. A mobile application was developed in an attempt to simplify and streamline these calculations. We compared the accuracy and speed of using the traditional pencil and paper technique with that using the Multiplier App (MA). METHODS: After attending a training lecture and a hands-on workshop on the MM and MA, 30 resident surgeons were asked to apply the traditional MM and the MA at different weeks of their rotations. They were randomized as to the method they applied first. Subjects performed calculations for 5 clinical exercises that involved congenital and developmental limb-length discrepancies and timing of epiphysiodesis. The amount of time required to complete the exercises and the accuracy of the answers were evaluated for each subject. RESULTS: The test subjects answered 60% of the questions correctly using the traditional MM and 80% of the questions correctly using the MA (P=0.001). The average amount of time to complete the 5 exercises with the MM and MA was 22 and 8 minutes, respectively (P<0.0001). CONCLUSIONS: Several reports state that the traditional MM is quick and easy to use. Nevertheless, even in the most experienced hands, performing the calculations in clinical practice can be time-consuming. Errors may result from choosing the wrong formulae and from performing the calculations by hand. Our data show that the MA is simpler, more accurate, and faster than the traditional MM from a practical standpoint. LEVEL OF EVIDENCE: Level II.

PRECICE® magnetically-driven, telescopic, intramedullary lengthening nail: pre-clinical testing and first 30 patients.

INTRODUCTION: Femoral/tibial lengthening with a telescopic, magnetically-powered, intramedullary nail is an alternative to lengthening with external fixation. METHODS: Pre-clinical testing was conducted of the PRECICE in a human cadaver. A retrospective review of the first 30 consecutive patients who underwent unilateral lengthening was also conducted. Nail accuracy was obtained by comparing the amount of nail distraction to the final bone length achieved at the end of the distraction process. Relative standard deviation of accuracy was used to calculate nail precision. RESULTS: Devices performed successfully in a human cadaver. Thirty consecutive patients (10 females, 20 males; mean age, 23 years) with limb length discrepancy (LLD) were followed an average of 19 months (range, 12-24 months). Etiology included congenital shortening (14), posttraumatic deformities (7), Ollier disease (3), osteosarcoma resection (1), prior clubfoot (2), hip dysplasia (1), post-septic growth arrest of knee (1), and LLD after hip arthroplasty (1). Twenty-four femoral and eight tibial nails were implanted. Mean preoperative lengthening goal was 4.4 cm (range, 2-6.5 cm); mean postoperative length achieved was 4.3 cm (range, 1.5-6.5 cm). Average consolidation index was 36.4 days/cm (range, 12.8-113 days/cm). Mean nail accuracy was 97.3% with a precision of 92.4%. Average preoperative and 12-month postoperative Enneking scores were 21.5 and 25.3 (p < 0.001), respectively. The preoperative and 12-month postoperative SF-12 physical and mental component scores were not statistically different. Nine complications (nine limb segments) resolved: two partial femoral unions, two suspected deep vein thrombosis (DVT), one delayed tibial union, one fibular nonunion, one peroneal nerve irritation, one knee joint subluxation, and one confirmed DVT. Twenty-nine (91%) of 32 limb segments achieved successful bone healing without revision surgery. DISCUSSION: Limb lengthening with PRECICE is reliable, but larger trials with longer follow-up will reveal limitations. Implantable nails prevent problems associated with external fixation, such as muscle tethering and pin-site infections.

Hip stability during lengthening in children with congenital femoral deficiency.

BACKGROUND: Congenital femoral deficiency (CFD) is one of the most challenging and complex conditions for limb lengthening. We focused on the problem of hip instability during femoral lengthening because subluxation and dislocation are potentially catastrophic for hip function. METHODS: We assessed for hip stability in 69 children (91 femoral lengthenings) who had CFD Paley type 1a (43 children) and 1b (26 children). The mean age at first lengthening was 6.4 years. RESULTS: Hip subluxation/dislocation occurred during 14 (15 %) of 91 lengthenings. Thirty-three pelvic osteotomies were performed before lengthening in an attempt to stabilize hips. Thirteen patients (type 1a, eight; type 1b, five) had acetabular dysplasia at initiation of lengthening. One of the eight with type 1a experienced mild femoral head subluxation; four of the five with type 1b experienced three dislocations and one subluxation. Eight patients (type 1b) experienced hip instability although they had pelvic osteotomies. Proximal femoral lengthening was a significant factor for hip subluxation. Patients with hip subluxation more likely underwent monolateral fixation and the original superhip procedure. Age ±six years was not a contributing factor for hip instability. CONCLUSIONS: Important risk factors for hip instability during femoral lengthening are severity of CFD, residual acetabular dysplasia, and proximal femoral lengthening. We recommend routine performance of pelvic osteotomy for patients with Paley type 1b CFD and distal lengthening. LEVEL OF EVIDENCE: Therapeutic Level IV.

Correction of Cubitus Varus After Pediatric Supracondylar Elbow Fracture: Alternative Method Using the Taylor Spatial Frame.

BACKGROUND: Cubitus varus is a well-reported complication of supracondylar fracture of the humerus potentially resulting in cosmetic problems, impaired function, and malpractice claims. Traditional methods of correcting malunited distal humeral fractures involve complex osteotomies that have a high complication rate, require a large exposure, and challenging fixation. We present a technique of gradual correction using a percutaneous transverse osteotomy and 3 dimensional correction with a Taylor Spatial Frame. METHODS: This was a retrospective, IRB-approved study of 12 patients between 2006 and 2010, with cubitus varus after a malunited pediatric supracondylar fracture. The average age at initial injury was 5+8 years. The average age of the patients at surgery was 8+8 years. We measured technical (radiographic parameters and complications), functional (clinical carrying angle, range of motion, QuickDash), and satisfaction domain (questionnaire) outcomes at a minimum follow-up of 6 months. RESULTS: The osteotomy healed in all patients by 10 weeks after the index surgery. The mean external fixator time was 10 weeks. The average preoperative and postoperative humeroulnar angles for the affected elbow were 23 degrees varus and 5.8 degrees valgus, respectively. This was statistically significant (P<0.001). The mean preoperative and postoperative carrying angles were 22 degrees of varus and 5.8 degrees of valgus. This was statistically significant (P<0.001). The results of the QuickDash assessment showed that patients were doing very well with regard to the use of their upper extremity. The mean symptom/disability score was 0.80. No major complications or neurovascular complications were encountered. Overall satisfaction with the procedure was high. CONCLUSIONS: The Taylor Spatial Frame as used in this case series provides the experienced surgeon another safe, accurate, and reliable method to correct cubitus varus after pediatric supracondylar fracture. We used in 7 of our 12 cases, a previously unreported pattern of distal humeral pin fixation that allows for a very distal metaphyseal osteotomy, close to the deformity apex. This is a biplanar delta configuration that straddles the olecranon fossa and is appropriate for both children and adults. LEVEL OF EVIDENCE: Level IV.

Custom Knee Device for Knee Contractures After Internal Femoral Lengthening.

The development of knee flexion contractures is among the most common problems and complications associated with lengthening the femur with an internal device or external fixator. Conservative treatment strategies include physical therapy, serial casting, and low-load prolonged stretching with commercially available splinting systems. The authors developed an individually molded, low-cost custom knee device with polyester synthetic conformable casting material to treat knee flexion contractures. The goal of this study was to evaluate the results of treatment with a custom knee device and specialized physical therapy in patients who had knee flexion contracture during femoral lengthening with an intramedullary lengthening femoral nail. This retrospective study included 23 patients (27 limbs) who underwent femoral lengthening with an internal device for the treatment of limb length discrepancy. All patients had a knee flexion contracture raging from 10° to 90° during the lengthening process and were treated with a custom knee device and specialized physical therapy. The average flexion contracture before treatment was 36°. The mean amount of lengthening was 5.4 cm. After an average of 3.8 weeks of use of the custom knee device, only 2 of 27 limbs (7.5%) had not achieved complete resolution of the flexion contracture. The average final extension was 1.4°. Only 7 of 27 limbs (26%) required additional soft tissue release. The custom knee device is an inexpensive and effective method for treating knee flexion contracture after lengthening with an internal device.

Lengthening With External Fixation Is Effective in Congenital Femoral Deficiency.

BACKGROUND: Treatment of congenital femoral deficiency is a complex, multistage protocol and a variety of strategies have been devised to address joint instability, limb length inequality, and deformities. Despite being an important part of the algorithmic approach to the overall treatment of patients with congenital femoral deficiency, a reproducible, safe, and functional treatment for femoral length discrepancy in patients with mild and moderate congenital femoral deficiency has not been reported. QUESTIONS/PURPOSES: (1) Does femoral lengthening by means of distraction osteogenesis, using a monolateral external fixator, result in effective lengthening without loss of hip or knee range of motion? (2) Does femoral lengthening cause an inhibition of femoral growth in patients with congenital femoral deficiency? (3) Do patients/families report satisfactory functional and emotional outcomes after undergoing femoral lengthening? (4) What proportion of patients develops complications after femoral lengthening with this technique? METHODS: Between 2005 and 2009, we evaluated 38 patients for femoral length discrepancy secondary to unilateral congenital femoral deficiency. Thirty-two patients completed treatment with distraction osteogenesis using a monolateral external fixator; general indications for this approach were congenital femoral deficiency Paley Types 1a, 1b, or 2a that had not previously undergone lengthening and had stable hip and knee joints. Of the 32 patients that completed treatment, 30 (94%) were available at a minimum of 2 years (mean, 3 years; range, 2-4.5 years) and were evaluated in this retrospective study. Preoperative and postoperative radiographic analysis, physiotherapy data, patient-based outcomes scores, and complications were reviewed for all eligible patients. Growth inhibition was measured using serial radiographs over the 2-year followup with the unaffected limb considered the norm. Functional and emotional outcomes were reported by adolescent patients or parents of younger children using the Pediatric Orthopaedic Society of North America Pediatric Outcomes Data Collection Instruments (PODCI), a validated patient-based outcomes measure. RESULTS: The mean distal femoral lengthening was 6 cm (SD ± 2 cm; range, 1.6-9 cm), for a mean percent of femoral length discrepancy correction of 112% (SD ± 55%; range, 15%-215%). Comparison of patient preoperative with postoperative mean hip and knee flexion and extension showed no difference with the numbers available (hip flexion: p = 0.219, mean difference of -5, 95% confidence interval [CI], 10, SD = 20; hip extension: p = 0.423, mean difference of -1, 95% CI, 2, SD = 5; knee flexion: mean difference of -7°, SD ± 29°, CI, 15, p = 0.467; knee extension: mean difference of -1°, SD ± 9°, CI, 4, p = 0.757). A comparison of the mean preoperative inhibition of 41% (range, -38% to 300%; SD ± 72; 95% CI, 29%) with the mean postoperative inhibition of 16% (range, -242% to 100%; SD ± 61%; 95% CI, 25%) for a mean postoperative stimulation of 25% (p = 0.055, SD ± 90%; 95% CI, 36%). In all six PODCI categories surveyed, patients had favorable standardized and normative scores, but patients who underwent femoral lengthening greater than 6 cm had both lower global functioning scores (90, SD ± 10 versus 96, SD ± 3, p = 0.043) and worse pain/comfort scores (79, SD ± 25 versus 96, SD ± 7, p = 0.029), and patients who had mean percent femoral lengthening greater than 25% of initial femur length had worse pain/comfort scores (79, SD ± 23 versus 97, SD ± 4, p = 0.012) with similar global functioning scores (90, SD ± 9 versus 96, SD ± 3, p = 0.058). The total number of postsurgical complications was 30 in 60 planned surgical procedures (50%). CONCLUSIONS: Our study results support the use of the described surgical technique for femoral lengthening in treating patients with congenital femoral deficiency. Additional studies are needed both to follow long-term patient-reported outcome measures, especially after a second or third lengthening, and to determine the effect of serial lengthening on the stimulation or inhibition of growth and rate of complications. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Internal lengthening device for congenital femoral deficiency and fibular hemimelia.

BACKGROUND: Patients with congenital limb shortening can present with joint instability, soft tissue contractures, and significant leg length discrepancy. Classically, lengthening is done with external fixation, which can result in scarring, pin site infection, loss of motion, and pain. We therefore developed an alternative to this approach, a new, controllable, internal lengthening device for patients with congenital limb shortening. QUESTIONS/PURPOSES: We evaluated this device in terms of (1) healing index, (2) complications, (3) accuracy of the device's external controller, and (4) adjacent-joint ROM. METHODS: Between January 2012 and May 2013, we treated 66 patients for congenital limb shortening, of whom 21 were treated using this device. During this period, general indications for using the device were patients with leg length discrepancies of 2 cm or more, with intramedullary canals able to withstand rods of at least 12.5-mm diameter and 230-mm length, without active infection in the affected bone, able to comply with the need for frequent lengthening, and without metal allergies or an implanted pacemaker. We included only those patients who had completed their course of treatment and were currently fully weightbearing, leaving 18 patients (21 bone segments) available for followup at a minimum of 6 months after limb lengthening (mean, 14 months; range, 6-22 months). Mean age was 19 years (range, 9-49 years). Sixteen femurs and five tibias were lengthened a mean of 4.4 cm (range, 2.1-6.5 cm). Mean distraction index was 1.0 mm/day (range, 0.5-1.8 mm/day). Healing index, complications, device accuracy, and ROM were recorded. To date, 10 of the 21 devices have been removed. This was typically done 12-24 months after insertion when the bone was solidly healed on all four cortices. RESULTS: Mean healing index was 0.91 months/cm (range, 0.2-2.0 months/cm). There were seven complications requiring an additional unplanned surgery, including one hip flexion contracture, three femurs with delayed healing, one tibia with delayed healing, one hip subluxation/dislocation, and one knee subluxation. The external controller was accurate as programmed and actual lengthening amounts were consistent. ROMs of the hip, knee, and ankle were essentially maintained. CONCLUSIONS: This device is completely internal, allowing for satisfactory joint motion during treatment in most patients. Lengthening was achieved in an accurate, controlled manner, and all patients reached their goal length. Complications remain a concern, as is the case with all approaches to this complex patient population. Both future comparative studies and longer-term followup are needed. LEVEL OF EVIDENCE: Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

The biomechanics of guided growth: does screw size, plate size, or screw configuration matter?

Guided growth with the eight-plate is a commonly used technique to correct angular limb deformities in children. However, the optimal combination of plate size, screw size, and screw configuration has not been determined. Using osteotomized femoral sawbones and a rail frame, we developed a growth model to examine the effect of these variables at 6-month, 12-month, and 18-month growth increments. The mean annual coronal plane change was 11.3°. Screw size and plate size were not associated with the rate of angular correction. Screw configuration was important, with parallel screws resulting in optimal correction at all time points compared with divergent screws (P<0.05).

Periscapular abscess: unusual cause of shoulder pain in children.

Periscapular abcess is an extremely rare clinical condition. Diagnosis and treatment can be delayed because the clinical picture often resembles septic arthritis of the shoulder. Early diagnosis and prompt surgical treatment are mandatory, as delayed treatment can be fatal due to sepsis. Previously, four cases of periscapular abcess were described in English literature. We describe two pediatric patients with periscapular abcess, who were treated surgically and healed without any complication.

Treatment of coxa brevis.

Coxa brevis of the hip results in a morphologic change of the proximal femur creating pain and fatigue, leg-length discrepancy, and altered gait. The most common cause is a growth alteration of the proximal femoral physis secondary to ischemic necrosis of the proximal femoral epiphysis. This article describes the Morscher osteotomy-a unique femoral neck-lengthening technique. The outcomes of this successful and predictable technique are resolution of symptoms of fatigue and hip discomfort; the absence of nonunion, infection, or hardware failure; and restoration of normal proximal femoral morphology and biomechanics.