Preoperative radius head dislocation affects forearm rotation after mobilization of congenital radioulnar synostosis.

BACKGROUND: The present study was carried out to answer three questions: 1) How much forearm rotation can be expected after mobilization of congenital radioulnar synostosis (CRUS)? 2) Does preoperative radius head dislocation affect forearm rotation after mobilization? 3) What factors other than radius head dislocation affect postoperative forearm rotation? METHODS: We performed mobilization of CRUS with a free vascularized fascio-fat graft and a radius osteotomy (Kanaya's procedure) on 26 forearms of 25 patients. The age at the surgery ranged from 5.3 to 13.4 years. The follow-up duration ranged 24-111 months. We classified CRUS into 3 groups according to the dislocation of the radius head: posterior dislocation (N = 13), anterior dislocation (N = 9) and no dislocation (N = 4). Since major complaints of patients and parents were poor forearm rotation and lack of supination, they were evaluated separately. RESULTS: Mean preoperative forearm ankylosis angle was 34.8° (range; neutral to 90° pronation). Preoperative pronation ankylosis angle was higher in the posterior dislocation group (mean 55.3°) than the anterior dislocation (mean 11.6°) and no dislocation groups (mean 5.0°). There was no re-ankylosis after mobilization and the mean postoperative active range of motion (ROM) was 86.5°. The mean active ROM was 75.7° in the posterior dislocation group, 96.1° in anterior dislocation group and 100.0° in no dislocation group. The mean active supination was 6.9, 33.9 and 47.5° respectively. The posterior dislocation group showed less ROM and less supination than other groups. Preoperative pronation ankylosis angle showed negative correlation with postoperative ROM (ρ = - 0.59) and postoperative supination (ρ = - 0.73). CONCLUSION: The mean postoperative active ROM of this mobilization was 86.5°. Posterior dislocation group showed higher pronation ankylosis angle preoperatively, and less postoperative ROM and less supination than anterior and no dislocation groups. Preoperative pronation ankylosis angle showed negative correlation with postoperative ROM and supination.

Identification of the third FGF9 variant in a girl with multiple synostosis-comparison of the genotype:phenotype of FGF9 variants in humans and mice.

Multiple synostosis syndrome (SYNS) is a heterogeneous group of genetic disorders mainly characterized by multiple joint synostosis due to variants in either NOG, GDF5, FGF9 or GDF6. To date, only two FGF9 variants have been associated with SYNS, characterized with hand and feet joint synostosis and fusion of the elbow and vertebral lumbar joints. Craniosynostosis was also observed in one family. Here, we report the clinical and radiological description of a young girl with a third heterozygous FGF9 variant, NM_002010.2:c.427A>T;p.(Asn143Tyr), which interestingly, is located at the same amino acid as the well characterized spontaneous Eks mouse variant. We also compare the genotype: phenotypes observed between humans and mice with SYNS.

A novel heterozygous variant in FGF9 associated with previously unreported features of multiple synostosis syndrome 3.

Human multiple synostoses syndrome 3 is an autosomal dominant disorder caused by pathogenic variants in FGF9. Only two variants have been described in FGF9 in humans so far, and one in mice. Here we report a novel missense variant c.566C > G, p.(Pro189Arg) in FGF9. Functional studies showed this variant impairs FGF9 homodimerization, but not FGFR3c binding. We also review the findings of cases reported previously and report on additional features not described previously.

Spondylocarpotarsal synostosis syndrome due to a novel loss of function FLNB variant: a case report.

BACKGROUND: Loss of function or gain of function variants of Filamin B (FLNB) cause recessive or dominant skeletal disorders respectively. Spondylocarpotarsal synostosis syndrome (SCT) is a rare autosomal recessive disorder characterized by short stature, fused vertebrae and fusion of carpal and tarsal bones. We present a novel FLNB homozygous pathogenic variant and present a carrier of the variant with short height. CASE PRESENTATION: We describe a family with five patients affected with skeletal malformations, short stature and vertebral deformities. Exome sequencing revealed a novel homozygous frameshift variant c.2911dupG p.(Ala971GlyfsTer122) in FLNB, segregating with the phenotype in the family. The variant was absent in public databases and 100 ethnically matched control chromosomes. One of the heterozygous carriers of the variant had short stature. CONCLUSION: Our report expands the genetic spectrum of FLNB pathogenic variants. It also indicates a need to assess the heights of other carriers of FLNB recessive variants to explore a possible role in idiopathic short stature.

Prevalence of Lumbosacral Transitional Vertebrae in Patients With Symptomatic Femoroacetabular Impingement Requiring Hip Arthroscopy.

PURPOSE: The primary aim of this study was to determine the prevalence of lumbosacral transitional vertebrae (LSTVs) in patients with symptomatic femoroacetabular impingement (FAI) requiring hip arthroscopy. The secondary aim was to determine whether there is an association between LSTV anatomy and patient-reported outcomes. METHODS: This retrospective study included patients aged 18 to 45 years with symptomatic FAI who underwent arthroscopy between March 2010 and March 2016 and had anteroposterior pelvic radiographs. The exclusion criteria included lack of an FAI diagnosis, hip osteoarthritis (Tönnis grade ≥ 2), prior spinal fusion surgery, prior total hip arthroplasty, indications for total hip arthroplasty, and revision surgery on the affected hip. All radiographs were assessed by an interventional spine and sports fellow. The primary outcome was the prevalence of LSTVs, classified using the criteria of Castellvi et al. Secondary outcomes included the modified Harris Hip Score, Hip Outcome Score, and International Hip Outcome Tool 33 score. RESULTS: A total of 1,880 patients were included. Review of the patients' radiographs yielded 262 LSTVs, for an overall prevalence of 13.9% (type IA in 104 [5.5%], type IB in 53 [2.8%], type IIA in 60 [3.2%], type IIB in 25 [1.3%], type IIIA in 8 [0.4%], type IIIB in 0 [0%], and type IV in 12 [0.64%]). The prevalence of type II, III, and IV LSTVs was 5.6% (n = 105). Unilateral LSTV sidedness did not correlate with symptom laterality (κ = 0.07). There were no differences in patient-reported outcomes between patients with LSTV anatomy and those without it. CONCLUSIONS: In this large cohort of 1,880 patients with symptomatic FAI, the prevalence of LSTVs was 13.9%. There was no correlation between sidedness of unilateral LSTVs and the symptomatic hip. Furthermore, there was no association between LSTV anatomy and patient-reported outcomes. The prevalence of LSTVs in this cohort was similar to the prevalence rates previously reported in patients with low-back pain. LEVEL OF EVIDENCE: Level IV, case series.

Application of 3-Dimensional Printing Technology in Rotational Osteotomy of Congenital Radioulnar Synostosis.

PURPOSE: To investigate whether computer-aided design (CAD) and 3-dimensional printing technology can assist in accurate completion of ulna-radius proximal rotational osteotomy in congenital radioulnar synostosis (CRUS). METHODS: We treated 1 right arm and 4 left arms of 4 boys with a mean age of 5.2 years (range, 4.3-6.0 years) between July 2018 and April 2019. Computed tomography (CT) scans of the forearm were performed on the children before surgery. Using the CT data, the pronation angle of the forearm was measured. An individualized dial with a matching forearm diameter was designed before surgery to control the angle of the rotational osteotomy. Ulna and radius models, and individualized dials, were prepared for each patient using 3-dimensional printing technology. Preoperative simulated surgery was performed using the 3-dimensional printed models. During the surgery, 2 Kirschner wires were used as operating levers for rotation, and rotational angle correction was precisely controlled using the dial. The cast and internal fixation were removed after x-ray examination showed that the osteotomy had healed, about 5 weeks after surgery. RESULTS: The rotational osteotomies were completed in a single operation, and the correction angle was 60°. No complications occurred after the operation. All patients showed functional improvements in activities of daily living. CONCLUSIONS: For CRUS patients, models and dials made with CAD and 3-dimensional printing technology can assist in precise rotational osteotomy. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic V.

Prospective Evaluation of Tarsal Coalition Excision Show Significant Improvements in Pain and Function.

BACKGROUND: Excision of pediatric tarsal coalition has been successful in most patients. However, some patients have ongoing pain after coalition excision. This study prospectively assessed patient-based clinical outcomes before and after surgical excision of tarsal coalition, with particular emphasis on comparison to radiologic imaging. METHODS: We prospectively studied 55 patients who had symptomatic coalition excision for 2 years postoperatively. Patients filled out the modified American Orthopaedic Foot and Ankle Society score, the University of California Los Angeles activity score, and the simple question "does foot pain limit your activity" at 4 different time points: preoperative, 6 months postoperative, 12 months postoperative, and 24 months postoperative. Comparisons were done utilizing patient demographics, imaging parameters, and patient-reported outcomes. RESULTS: Compared with preoperative levels, patients showed improvements in all outcome parameters. Patients with calcaneonavicular coalitions showed initial rapid improvement with later slight decline, while patients with talocalcaneal coalitions showed more steady improvement; both were similar at 2 years postoperatively. CONCLUSIONS: This prospective study demonstrated remarkable clinical improvements after tarsal coalition excision regardless coalition type, though postoperative courses differed between calcaneonavicular and talocalcaneal types. Finally, a subset of patients has ongoing activity limiting foot pain after coalition excision which could not be explained by the data in this study. LEVEL OF EVIDENCE: Level II-prospective cohort study.

Arthroscopic Calcaneonavicular Coalition and Too-long Anterior Process of the Calcaneus Resection in Children.

Persistent symptomatic calcaneonavicular coalition (CNC) and too-long anterior process of the calcaneus (TLAP) are congenital disorders that can benefit from surgical treatment. The arthroscopic technique for CNC and TLAP resection has previously been described. The aim of this prospective study was to describe outcomes following arthroscopic resection of 12 (38.71%) CNC and 19 (61.29%) TLAP cases in 30 consecutive pediatric patients treated between July 2009 and March 2013. There mean age was 12.4 (range 10 to 15) years, and the mean follow-up was 55.2 (range 24 to 79) months. Radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot Scores, AOFAS pain scores, and patient satisfaction were assessed. All final postoperative imaging scans revealed complete synostosis resection without recurrence. The mean overall AOFAS Ankle-Hindfoot Score increased from 78.87 (95% confidence interval [CI] 76.74 to 81.01) to 93.06 (95% CI 91.10 to 95.03) (p < .001). All patients showed pain reduction after surgery; even 1 patient (3.23%) who initially developed complex regional pain syndrome eventually had a successful outcome. The mean AOFAS pain score increased from 23.87 (95% CI 22.05 to 25.69) to 34.84 (95% CI 32.97 to 36.70) (p < .001). All patients were either satisfied (n = 9 [30%]) or very satisfied (n = 21 [70%]) with the intervention at the final follow-up. Although both arthroscopic CNC and TLAP resection are demanding techniques, they allow for precise coalition resection through a less invasive approach, which may ultimately lead to faster recovery and improved outcomes.

Bilateral Proximal Tibiofibular Synostosis Caused by Osteochondroma in a 21-Year-Old Highly Active Male-First in Literature.

Background and Objectives: Up until now, only one case of unilateral proximal tibiofibular synostosis caused by osteochondroma has been reported. This report is the first well-documented bilateral case of proximal tibiofibular synostosis caused by an osteochondroma. Case Report: A 21-year-old, highly active male patient with bilateral proximal tibiofibular synostosis caused by an osteochondroma suffering from persistent knee pain is presented. As conservative methods had failed, the patient was treated by bilateral open resection of the connecting bone. Histopathological findings confirmed the preoperative diagnosis. The patient returned to sports three weeks after surgery and continued soccer training six weeks after surgery. Discussion: The case report presents the successful treatment of a bilateral proximal tibiofibular synostosis caused by an osteochondroma by bilateral open resection of the connecting bone.

Chronic dysphagia caused by Laryngo-vertebral Synostosis after anterior fusion for cervical spine trauma: a case report.

BACKGROUND: Anterior cervical spine surgery is often associated with postoperative dysphagia, but chronic dysphagia caused by laryngo-vertebral synostosis is extremely rare. We report a case of chronic dysphagia caused by synostosis between the cricoid cartilage and cervical spine after anterior surgery for cervical spine trauma. CASE PRESENTATIONS: We present a case of a 39-year-old man who had sustained complex spine trauma at C5-6 associated with complete spinal cord injury at the age of 22; the patient presented with a 5-year history of chronic dysphagia. Computed tomography demonstrated posterior shift of the esophagus as well as calcification of the cricoid cartilage and its fusion to the right anterior tubercle of the C5 vertebra. A barium swallow study demonstrated significant barium aspiration into the airway and no laryngeal elevation. The patient underwent resection of the bony bridge and omohyoid muscle flap insertion. His symptoms ameliorated after surgery. CONCLUSION: Synostosis between the cricoid cartilage and cervical spine may occur associated with cervical spine trauma and causes chronic dysphagia. Resection of the fused part can improve dysphagia caused by this rare condition and omohyoid muscle flap might be a good option to prevent recurrence.

The radiological diagnosis of extra-articular posteromedial talocalcaneal coalition.

OBJECTIVES: Extra-articular posteromedial talocalcaneal coalition (EA-PM TCC) accounts for approximately one-third of TCC, but its radiographic features are not well-described. The current study aims to compare the radiographic features of EA-PM TCC with normal ankles and with the commoner forms of TCC. MATERIALS AND METHODS: A retrospective review of cases of TCC over 12 years for whom radiographs, CT, and/or MRI study were available. Radiographs were assessed by 2 radiologists for the presence of the C-sign, talar beak, dysmorphic sustentaculum, absent middle facet, and prominence of the posterior subtalar joint. TCC was classified by a third radiologist based on CT/MRI findings into 3 groups: no TCC, EA-PM TCC, and other TCCs. The radiographic findings for the 3 groups were compared. RESULTS: The study included 50 patients, 28 males and 22 females with a mean age of 21.1 years (range 8-70 years). In 15 patients, both ankles had been imaged, resulting in a total of 65 cases. In 17 ankles, no TCC was identified, while 15 ankles were classified as EA-PM TCC and 33 as having other types of TCC. There were no statistically significant differentiating radiological features between the groups with no TCC and EA-PM TCC apart from prominence of the posterior subtalar joint, while only the C-sign allowed identification of patients with other types of TCC. CONCLUSIONS: The study suggests that EA-PM TCC cannot be diagnosed based on the classical indirect radiological signs of TCC, but can be identified by prominence of the posterior subtalar joint.

Radial Pronation Angle: A Novel Radiological Evaluation Index of Congenital Proximal Radioulnar Synostosis.

INTRODUCTION: Congenital proximal radioulnar synostosis (CPRUS) is a relatively rare forearm deformity that is characterized by a fixed pronated forearm of varying severity. The osseous synostosis between the proximal part of the ulna and the radius can be seen on the X-ray images in most cases. Many researchers have attempted to identify methods to measure the disease severity to guide in the treatment of CPRUS. However, to describe the overall deformity, the use of multiple indicators is essential, and some of these measurements require special software or need to be conducted on cadavers. OBJECTIVE: The aim of the current study was to introduce the radius pronation angle (RPA), a novel radiological evaluation index of CPRUS, and analyze the relationship between the RPA and the severity of the deformity. METHODS: Three-dimensional models of 43 CPRUS forearms (19 left forearms and 24 right forearms) of 32 patients (23 males and 9 females; average age was 6 years 8 months; range, from 1.5 to 27 years) treated at Beijing Ji Shui Tan Hospital during 2016 to 2019 were reconstructed using a computer-assisted technique. The special flexed posterior-anterior views of the X-ray image (the f-PA view) of the forearms were obtained, and the forearm rotation angle and the ulnar inner rotation angle were measured on each forearm. The RPA was measured on the f-PA view, and the lengths of the osseous synostosis, ulna, and the radial head were measured on the computed tomography scan images using the multiplanar reconstruction function. The Pearson index was analyzed between the RPA and the other measurements. RESULTS: The RPAs were correlated with the forearm rotation angle, ulnar inner rotation angle, relative length of the osseous synostosis, and the relative length of the radial head (P < 0.05). CONCLUSIONS: The RPA can be measured quickly and easily on the f-PA view of the X-ray image and can be used as a reliable indicator of the severity of CPRUS.

Post-traumatic proximal radioulnar synostosis: results of surgical treatment and review of the literature.

BACKGROUND: Post-traumatic proximal radioulnar synostosis is a very rare and disabling condition whose surgical treatment has traditionally been viewed with pessimism. The results of the few case series in the literature are conflicting. Our aims were (1) to describe the clinical results of a case series treated surgically by a single elbow surgeon and (2) to review the literature. METHODS: Twelve patients were evaluated. Preoperative radiographs and computed tomography scans were performed. According to the Viola and Hastings classification, there was 1 case of type IC synostosis; 3, type IIA; 2, type IIIA; and 8, type IIIB. Two patients had a double synostosis. The synostosis was excised in 10 cases; in addition, radial head excision, radial head arthroplasty, and proximal radial diaphyseal resection were performed in 1, 3, and 2 cases, respectively. The Mayo Elbow Performance Score, modified American Shoulder and Elbow Surgeons score, and QuickDASH (short version of Disabilities of the Arm, Shoulder and Hand questionnaire) score were used for the preoperative and postoperative evaluation. The nonparametric Wilcoxon signed rank test was used for the statistical analysis. RESULTS: The mean follow-up period was 20.5 months. The final mean extension-flexion and pronation-supination arcs were 116° and 123°, respectively. Significant improvements were found in the Mayo Elbow Performance Score (P = .005), modified American Shoulder and Elbow Surgeons score (P = .012), and QuickDASH score (P = .002), with mean values of 24, 28, and 17, respectively. One synostosis recurrence and one late disassembly of the radial head arthroplasty were observed. CONCLUSIONS: Post-traumatic proximal radioulnar synostosis surgery is effective, but careful preoperative planning based on the pathoanatomic characteristics of each type of synostosis and associated lesions is mandatory. Synostosis excision is performed in most cases, whereas additional surgical procedures should be considered in selected cases.

Functional and Radiological Outcomes After Tarsal Coalition Resections: A Minimum 5-Year Follow-Up.

Few studies have evaluated the long-term functional and radiological outcomes of tarsal coalition resections. This study aimed to report and compare the functional and radiological outcomes after talocalcaneal (TC) and calcaneonavicular (CN) coalition resections. Thirty-three patients between 12 and 35 years old with symptomatic tarsal coalitions participated, each undergoing tarsal coalition resections (24 TC and 9 CN). The range of motion, visual analog scale score, American Orthopedic Foot and Ankle Society hindfoot scale, Maryland foot score, tripod index, and modified Kellgren-Lawrence scale for subtalar osteoarthritis were used to evaluate the functional and radiological outcomes. The mean age at the time of surgery and mean follow-up in the TC group were 17.8 ± 5.6 years (range 13 to 35) and 6.2 ± 1.7 years (range 5 to 12), respectively, and 16.0 ± 4.4 years (range 12 to 23) and 7.7 ± 3.0 years (range, 5 to 12) in the CN group. There was no difference in the range of motion, outcome scores, tripod index score, and modified Kellgren-Lawrence scale score between patients in the 2 groups. A positive correlation was noted between the size of the TC coalition, coalition/joint surface ratio, and hindfoot valgus angle regarding outcome scores. However, there was no association between the modified Kellgren-Lawrence scale score and outcome scores. At the minimum 5-year follow-up, the functional and radiological outcomes were similar between TC and CN resections. Subtalar joint osteoarthritis developed in all patients with TC resections and most patients with CN resections, but patients did not have functional impairment.

Length of synostosis and segmented intracranial volume correlate with age in patients with non-syndromic sagittal synostosis.

PURPOSE: The aim of this study is to compare the length of synostosis and segmented intracranial volume (SIV) with age in children with non-syndromic sagittal synostosis. METHODS: Thirty-three consecutive patients (22 boys) who had been operated by cranial vault remodeling because of sagittal synostosis were compared retrospectively from 3D-CT imaging data sets obtained from volumetric CT. The mean age of the patients at preoperative CT imaging was 0.49 (range 0.13-1.3) years and at 1-year postoperative imaging 1.8 (range 1.3-3) years. The mean interval between preoperative CT imaging and surgery was 0.25 (range 0-0.8) years. Pearson's correlation and Student's t test were used in the statistical analyses. RESULTS: Length of sagittal synostosis correlated positively with age at preoperative CT (r = 0.688, p < 0.01). Children with total synostosis (n = 9) were significantly older (mean age 0.74 vs. 0.4 years, p < 0.01) than those with partial synostosis. Of partial synostoses, 9 were located anteriorly, 3 in the middle, and 12 posteriorly. The mean synostosis ratio (synostosis length/total sagittal suture length × 100) was 83%. Preoperative SIV correlated positively with age at preoperative CT (r = 0.788, p < 0.01), whereas the 1-year postoperative SIV did not correlate with age at operation. The older the child at the time of the operation, the less the percentage SIV increased. CONCLUSIONS: Length of sagittal synostosis and SIV increased with age.

The "Double Medial Malleolus": A New Physical Finding in Talocalcaneal Coalition.

PURPOSE: It has been the observation of the senior author that there is a bony fullness or "double medial malleolus" over the middle facet as a consistent finding with most talocalcaneal coalitions (TCC). To document this observation, we reviewed records and radiographs in 3 patient groups. METHODS: Part 1: retrospective chart review was completed for 111 feet to determine the clinical presence of a palpable "double medial malleolus." Part 2: computed tomography (CT) scans for evaluation of tarsal coalition or symptomatic flatfoot between January 2006 and December 2014 were retrospectively reviewed for the same cohort. Soft tissue thickness was measured as the shortest distance between bone and skin surface at both the medial malleolus and the middle facet/coalition. The volume of the middle facet or coalition was measured at their midpoint. These findings were compared among feet with TCC (n=53), calcaneonavicular coalition (CNC) (n=20), and flatfoot (n=38). RESULTS: Part 1-clinical: from medical records, 38 feet (34%) had documented record of a palpable medial prominence. Of the feet reviewed with a "double medial malleolus," all had TCC (no false positives or false negatives). Clinical and CT prominence demonstrated significant correlation (rs=0.519, P=0.001). Part 2-radiographic: CT observation of "double medial malleolus" is significantly associated with TCC (P<0.001). CT observation of double medial malleolus is 81% sensitive and 79% specific as a predictive test for TCC. The middle facet-to-skin distance was significantly closer in those with TCC versus controls (P<0.001). The ratio was larger in patients with TCC versus CNC (P=0.006) or flatfeet (P<0.001). Volume was nearly twice the size in patients with TCC versus the controls (P<0.001). CONCLUSIONS: TCCs have a bony prominence below the medial malleolus on clinical exam and CT scan not present in flatfeet or CNCs. This abnormal middle facet is almost twice the size of the normal middle facet. Obesity or severe valgus may mask this finding. If a palpable bony prominence is noted just below the medial malleolus during examination of a painful foot with a decrease in subtalar motion, the likely diagnosis is TCC. With this added clinical finding, appropriate images can be ordered to confirm the diagnosis of the latter. We advise CT scans with 3D images for surgical planning. The primary finding for tarsal coalitions in textbooks is decreased subtalar motion. This new finding of a palpable enlarged medial prominence just below the medial malleolus is highly associated with TCCs. LEVEL OF EVIDENCE: Level III.

Three-Dimensional Analysis of Hemimetameric Segmental Shift in Congenital Scoliosis.

STUDY DESIGN: This is a retrospective cohort study. BACKGROUND: Hemimetameric segmental shift (HMMS) is defined as a hemivertebral deformation in which 2 or more hemivertebrae exist on both sides of the spine and are separated by at least 1 normal vertebra. Reports of HMMS are rare and based on simple anterior x-ray images. No reports have used 3-dimensional computed tomography (3D-CT) to analyze both the anterior and posterior elements. The objective of this study was to analyze the morphology and clinical features of HMMS 3 dimensionally. METHODS: HMMS was confirmed in 32 (6.6%, 16 males and 16 females) of 483 patients diagnosed with congenital scoliosis at the study institution between 1998 and 2013. The average age at the first visit was 6 years and 3 months. 3D-CT imaging was performed for 30 patients older than 2 years (average age: 9 y and 8 mo) and used to classify cases according to posterior elements. RESULTS: With regard to the number of hemivertebrae present, 21 patients had 2 hemivertebrae, 7 patients had 3 hemivertebrae, and 2 patients had 4 hemivertebrae. Patients with 2 hemivertebrae predominantly had hemivertebrae in the thoracolumbar spine. Patients were classified into 2 categories: malformation existing at an equal level in anterior and posterior sides (unison HMMS) and malformation existing at nonequal levels (discordant HMMS). Nine patients had unison HMMS and all of them had 2 hemivertebrae (average: 4.6 vertebrae). Twenty-one patients had discordant HMMS, with 12 having 2 hemivertebrae, 7 having 3 hemivertebrae, and 2 having 4 hemivertebrae. CONCLUSIONS: Through 3D-CT analysis, HMMS was categorized as unison or discordant. Discordant HMMS was observed in 21 of 30 (70%) patients and in all patients with >3 hemivertebrae. Diagnosing HMMS, whether unison or discordant, is clinically important and should be done with careful analysis of bone models and/or radiologic images to determine the correct spinal levels. LEVEL OF EVIDENCE: Level IV-diagnostic study.

Carpal Coalitions on Radiographs: Prevalence and Association With Ordering Indication.

PURPOSE: Carpal coalitions are common and usually incidental to the indication for wrist radiographs. It is not clear if, or when, carpal coalitions cause pain. The aim of this study was to assess the prevalence of incidental carpal coalitions by evaluating radiographs taken for various indications and to test the association of demographic variables and ordering indications with the finding of a carpal coalition. METHODS: We reviewed 1,119 posteroanterior wrist radiographs for the presence of carpal coalition. We used bivariate and multivariate analyses to assess demographic factors for their independent associations with the presence of carpal coalitions and to compare the difference in the prevalence of carpal coalitions between radiographs obtained to evaluate traumatic wrist pain (623 wrists), nontraumatic wrist pain (175 wrists), and other reasons (321 wrists). RESULTS: Radiographs of 98 out of 1,119 patients (8.8%) showed a carpal coalition. Carpal coalitions were equally likely on radiographs obtained for traumatic wrist pain and nontraumatic wrist pain. Patients with no wrist trauma or wrist pain were less likely to have a carpal coalition on their radiograph. CONCLUSIONS: We consider carpal coalitions an unlikely cause of wrist pain. The lower prevalence in radiographs obtained for causes other than wrist trauma or wrist pain remains unexplained, although it may be spurious. In the evaluation of a patient with nonspecific wrist pain, clinicians should be careful ascribing symptoms to anatomical variations on radiographs. These incidental findings should not usually affect management. TYPE OF STUDY/LEVEL OF EVIDENCE: Diagnostic III.