A 16-year-old male presented with a difficulty in walking (gait disturbance) and a deformity of both lower limbs. On examination, the patient was found to be free of H/O pain, anaemia. A plain X-ray investigation showed that he did not have hepatosplenomegaly.
A 16-year-old male presented with a difficulty in walking (gait disturbance) and a deformity of both lower limbs. There was no history of associated pain. On examination, it was noted that he had neither anaemia nor organomegaly. An X-ray examination of the knee joint revealed splaying of the distal femur and the proximal tibia. Successive X-rays of the upper limbs were taken and the films revealed metaphyseal flaring extending into the diaphysis, which suggested he had Erlenmeyer Flask deformity. Splaying of the proximal and the distal end of the long bones with a thinned out cortex and relative constriction of the central portions of the shaft were seen. The X-ray photographs of his skull appeared to be normal.
An Erlenmeyer flask appearance is seen in Gaucher's disease, certain anaemias, fibrous dysplasia, the Niemann–Pick disease, craniometaphyseal dysplasia, Pyle's (or metaphyseal) dysplasia, heavy metal poisoning and osteopetrosis. Pyle's (metaphyseal) dysplasia is known to be a rare disorder that shows either recessive or dominant transmission. This disorder may manifest at any age and usually presents with mild clinical symptoms or is at times asymptomatic. Clinical symptoms include joint pain, muscular weakness, scoliosis, genu valgum, dental malocclusion and bone fragility. It has a characteristic radiologic appearance as described above. The skull is virtually spared although minor alterations in the skull such as prominent supra orbital ridges, obtuse angle of the jaw, mild sclerosis of the cranial vault may be seen. The ribs and medial portions of the clavicles may also show expansion. Radiological changes in the spine varying from moderate platyspondyly to bodies having the appearance of a biconcave lens have been reported. Important differentials include the other types of metaphyseal dysplasia such as the Jansen, Schmid and McKusick types which are associated with a short stature, skull changes, vertebrae and rib changes and cartilage hair hypoplasia. Cartilage hair hypoplasia (CHH) is an autosomal recessive inherited disorder that results in short limb dwarfism, sparse hair and is predominantly associated with T-cell immunodeficiency. Craniometaphyseal dysplasia is the most commonly confused condition. The basic features of both the autosomal dominant and the recessive forms are facial deformity, cranial hyperostosis and the failure of normal modelling of tubular bones. Radiologically, progressive sclerosis of the base of the skull and about the cranial sutures, obliteration of the paranasal sinuses and a loss of lamina dura about the teeth are seen. Remodelling defects in the long bones manifested as metaphyseal expansion, cortical thinning and club shaped epiphyses are also seen. Gaucher's disease is characterized by hepatosplenomegaly with widespread osteopenia with a coarsened trabecular pattern. Focal osteosclerosis, ischemic necrosis of the proximal capital femoral epiphyses, periosteal reaction and endosteal scalloping are also noted in Gaucher's disease. Fibrous dysplasia and osteopetrosis have characteristic radiological findings. Patients with anaemia and heavy metal poisoning commonly have irregular transverse radiodense lines near the ends of the long bones, which is however not specific. The characteristic Erlenmeyer flask deformity with no changes in the skull radiograph would narrow down the diagnosis to Pyle's dysplasia.
Pyle's metaphyseal dysplasia.
1. From the provided X-rays of the lower limbs and forearms, the bilateral metaphyses of the long bones show marked “flask-like” expansions, i.e., the classic Erlenmeyer flask deformity.
2. The cortical bone is relatively thin, and the metaphyseal regions gradually flare outward, but no obvious bony destruction or fracture lines are observed.
3. The medullary cavity is widened, and the trabecular pattern appears relatively loose, without notable sclerosis or patchy changes.
4. No evident skull thickening, skull base sclerosis, or craniofacial deformities have been observed at this time.
5. Bilateral hand X-rays indicate that neither the phalanges nor the metacarpal bones exhibit significant sclerosis or thickening; the metaphyses do show some expansion, but the basic bony contour remains preserved.
Given the patient’s bilateral lower limb deformities, absence of significant hepatosplenomegaly, and the X-ray findings of a classic Erlenmeyer flask deformity, the following diagnoses may be considered:
1. Pyle-type (Metaphyseal) Dysplasia: This condition most commonly presents with flask-shaped metaphyseal widening and thinning of the cortical bone. Skull involvement is usually mild or minimal. Clinical symptoms tend to be mild but may include abnormal gait and lower limb deformities.
2. Gaucher Disease: It typically involves hepatosplenomegaly, osteoporosis, and coarse trabecular patterns. However, this case shows no obvious hepatosplenomegaly or the typical bony changes (such as endosteal scalloping or focal sclerotic lesions), making Gaucher disease less likely.
3. Craniometaphyseal Dysplasia: Often presents with marked skull and facial bone thickening, skull base sclerosis, and possible sinus obstruction. In this case, there is no significant skull thickening or sclerosis, thus reducing the likelihood of this diagnosis.
4. Others: Conditions such as chondrodysplasia (Jansen, Schmid, McKusick types), Niemann-Pick disease, fibrous dysplasia, and osteopetrosis can also show skeletal deformities or characteristic X-ray findings. However, correlating the clinical features with the known imaging presentations, these are not entirely consistent with the patient’s presentation.
Considering the following:
• 16-year-old male with walking difficulties and lower limb deformities
• Lack of significant pain or hepatosplenomegaly
• X-ray findings of a classic Erlenmeyer flask deformity in long bones, with minimal or no skull involvement
In conclusion, the most likely diagnosis is: Pyle-type (Metaphyseal) Dysplasia.
1. Treatment Strategy
• Generally, Pyle-type dysplasia patients present with mild symptoms. If the deformity is pronounced and affects function, orthopedic interventions such as osteotomies for correction may be considered.
• In the event of joint pain or restricted range of motion, nonsteroidal anti-inflammatory drugs (NSAIDs) may be used under medical supervision.
• Regular follow-up is advised to monitor bone development and lower limb alignment, assessing any progression of deformities.
2. Rehabilitation/Exercise Prescription (FITT-VP Principle)
• Frequency (F): Engage in rehabilitation exercises or fitness training 3–5 times per week.
• Intensity (I): Begin with low-intensity activities (e.g., aquatic walking, gentle muscle-strengthening) and gradually progress to moderate intensity.
• Time (T): Start with 15 minutes per session and gradually increase to 30–45 minutes, adjusting based on individual tolerance.
• Type (T): Prioritize low-impact aerobic exercises in water, mild lower limb resistance training, and range-of-motion exercises to reduce stress on weight-bearing joints.
• Progression (P): As the condition and muscle strength improve, incrementally add resistance training and core stabilization exercises, such as using resistance bands or light dumbbells to strengthen the lower limbs and trunk.
• Precautions (P):
- Avoid high-impact activities (e.g., running, jumping) to prevent excessive stress on bones or joints.
- Discontinue exercise and consult medical personnel if significant pain occurs during training.
- Periodic reassessment of skeletal status and correction outcomes is necessary to adjust the exercise plan dynamically.
This report is a reference analysis based on the provided imaging studies and basic clinical information. It does not replace an in-person consultation or professional medical opinion. The actual diagnosis and treatment plan must integrate the patient’s comprehensive medical history, physical examination, and additional tests, with final decisions made by qualified healthcare professionals.
Pyle's metaphyseal dysplasia.
