Hemophilic pseudotumor of the first lumbar vertebra.

Hemophilic pseudotumor involving the spine is extremely uncommon and presents a challenging problem. Preoperative planning, angiography, intra and perioperative monitoring with factor VIII cover and postoperative care for hemophilic pseudotumor is vital. Recognition of the artery of Adamkiewicz in the thoracolumbar junction helps to avoid intraoperative neurological injury. We report the case of a 26-year-old male patient with hemophilia A, who presented with a massive pseudotumor involving the first lumbar vertebra and the left iliopsoas. Preoperative angiography revealed the artery of Adamkiewicz arising from the left first lumbar segmental artery. Excision of pseudotumor was successfully carried out with additional spinal stabilization. At 2 years followup, there was no recurrence and the patient was well stabilized with a satisfactory functional status. Surgical excision gives satisfactory outcome in such cases.

INTRODUCTION

Hemophilic pseudotumor is an uncommon complication in hemophilic patients with clotting factor (VIII or IX) <1% of normal level (moderate to severe hemophilia) and has a reported incidence of 1-2%.12

We report a patient of hemophilic pseudotumor affecting the first lumbar vertebra and the left iliopsoas muscle. To the best of our knowledge, a similar case has not been reported in English literature. Preoperative angiography revealed the first left lumbar segmental artery as the predominant blood supply through the artery of Adamkiewicz. This important factor influenced our surgical decision making in this patient.

CASE REPORT

A 26-year old male patient, known case of hemophilia A presented with complaints of sudden onset progressive midback pain and left lower limb weakness following lifting a heavy weight 2 months prior to the presentation. The primary diagnosis was made at the age of 4 years. He had earlier developed a right psoas hematoma following blunt trauma to the right side of the abdomen in 1996. This was treated with factor VIII infusion. Since 1997, he had recurrent episodes of bilateral hip pain, which were treated with analgesics and local ice application. Earlier he had two episodes of hemarthroses, which were treated with transfusion of fresh frozen plasma.

Clinical examination revealed a large intraabdominal mass measuring about 25 × 11 cms and occupying the left half of the abdominal and the pelvic cavity. The surface of the mass was irregular with a variable consistency. There was some tenderness at the spinous process of the first lumbar vertebra. Lumbar spine movements were restricted due to pain. The patient was ambulant with the support of a cane. Motor examination was normal and the sensory examination revealed 50% sensory deficit over L5 and S1 dermatomes on both the lower limbs. Examination of the appendicular joints revealed bilateral elbow stiffness with fixed flexion deformity of 30° on the right side and 20° on the left side with bilateral knee arthritis and bilateral ankle equinus of 10°.

Factor VIII assay showed <1% of normal. Activated partial’ thromboplastin time was 95.5 s, Factor VIII inhibitor (Bethesda) assay was negative and viral screening was positive for HCV infection. Renal and liver function tests were within normal limits.

Plain radiographs of thoracolumbar spine showed well defined expansile osteolytic lesion with endosteal scalloping involving the L1 vertebral body and its posterior elements. Plain radiographs also revealed an osteolytic lesion involving the anterior border of second lumbar vertebral body [Figure 1a and b].

Figure 1

(a) Preoperative radiograph thoracolumbar spine (anteroposterior view) showing partial destruction and collapse of L1 vertebral body (black arrow) (b) Lateral radiograph showing endosteal scalloping of L1 vertebra

Magnetic resonance imaging (MRI) revealed a large cystic mass involving the left iliopsoas muscle, extending from L1 vertebral body into the left side of the pelvic cavity, the walls of which were thick and hypo intense suggestive of hemosiderin deposits. Intraosseous pseudotumor of L1 vertebra with partial collapse and destruction of most of the body and left pedicle, lamina and spinous process was seen. Pseudotumor arising from L1 vertebral body with extension into the epidural space and bilateral neural foramen leading to severe compression of dural sac and exiting nerve roots was noted [Figure 2a-c].

Figure 2

Preoperative T2 weighted (a) sagittal (b) coronal and (c) axial magnetic resonance images of pseudotumor showing craniocaudal extension of cyst and cranially displaced kidney

Selective lumbar segmental arteriogram showed moderate vascularity of the pseudotumor. Artery of Adamkiewicz was arising from the left first lumbar segmental artery [Figure 3]. Right L1 vertebral artery and left L3 arteries were selectively cannulated and embolized with 500-700 micron polyvinyl alcohol particles until it angiographically attained stasis 1 day prior to surgery. The left first lumbar segmental artery was not embolized considering the risk of postembolization neurological deficit.

Figure 3

Preoperative selective left lumbar arteriogram showing hairpin bend arteriole (artery of Adamkiewicz) (arrow)

Factor VIII transfusion was given before embolization and on the day of surgery. The factor level achieved was 73% (2020 IU) before embolization and 111.9% (2620 IU) prior to surgery. Trans-urethral stenting of the left ureter was done. Under general anesthesia, posterior stabilization of spine (D11 to L3) was performed with a pedicle screw and rod construct. Through a left anterolateral retro-peritoneal approach the iliopsoas pseudotumor was excised. The surgical incision was made along the left 11th rib to approach the L1 body. Incision was then extended downwards in an oblique manner up to the left iliac fossa, as the mass was large and extending below the level of inguinal ligament. Excision of the mass was performed retroperitonealy. The intraoperative findings were a large (20 × 8.5 × 6 cms), lobulated tumor mass of variable consistency [Figure 4] extending supero inferiorly from left side of L1 vertebral body up to the left pelvic cavity below the level of left inguinal ligament and medio laterally from the left lumbar region reaching up to the midline. The left ureter, peritoneum, large vessels and lumbar plexus were firmly adherent to the pseudotumor wall. Ureter was displaced ventromedially and the lumbar plexus was passing through the pseudotumor. All these vital structures were meticulously dissected and separated from the tumor mass. While dissecting the left common iliac artery and vein from the tumor mass, both the (internal and external iliac) vessels tore at the junction. The artery was repaired and the vein was ligated. The L1 body pseudotumor was not excised in toto, only the soft tissue component was resected. The left first lumbar segmental artery was preserved. Duration of surgery was 10 hours and the blood loss was 3.5 L. Blood loss was replaced with 1750 mL of whole blood and 1000 mL of rejuvenated red cells intraoperatively and postoperatively patient received 600 mL of rejuvenated red cells.

Figure 4

Macroscopic picture of the surgical specimen with lobulated surfaces

Postoperatively the factor level was maintained above 80% for first 3 days, 50-80% up to 8th postoperative day, 30-50% up to 14th postoperative day. Total factor received for the surgery was 36,162 IU (565 IU/kg). Empirical antibiotics were administered until suture removal.

Macroscopic examination revealed a large oblong mass measuring 20 × 8.5 × 6 cm mass with irregular bosseleated outer surface with large dilated veins over the same. The margins (except the superior margin) were smooth and well defined. It had variable consistency. “Chocolate like” material (due to blood clots) was found on the cut section of the mass. Multiloculated cysts containing blood clots were noted. The largest cyst being 11 cm in the maximum diameter with a thickness of 0.7 cm. Microscopic examination revealed that the cyst wall was composed of extensively hyalinized fibrous tissue lined on one aspect by inflammatory granulation tissue with numerous hemosiderophages. The wall revealed mild chronic inflammation and areas of old hemorrhage confirming a diagnosis of hemophilic pseudotumor [Figure 5].

Figure 5

Photomicrographs showing inflammatory granulation tissue with hemosiderophages and evidence of old hemorrhages (×200)

At 1 year and subsequently at 2 years followup, patient was doing well both clinically and functionally without any residual pain, discomfort or disability. He had returned back to his employment. Plain radiographs showed spinal stabilization in situ with no vertebral body collapse or progression of deformity [Figure 6a and b]. MRI revealed small residual tumor at L1 vertebral body, which was comparable to the preoperative picture [Figure 7a and b]. Followup computerised tomogram showed sclerosis of L1 body [Figure 8a and b].

Figure 6

Postoperative radiographs of thoracolumbar spine (a) anteroposterior (b) lateral views showing spinal stabilization with pedicle screws and rods with no progression of deformity

Figure 7

(a-b) Followup magnetic resonance imaging (sagittal and axial views) showing residual tumor at L1 vertebra and no recurrence of tumor

Figure 8

(a-b) At 2 years followup computed tomography scan (sagittal and axial views) revealing sclerosis of the vertebral body wall

DISCUSSION

Pseudotumor was first described by Starker in 1918.3 This usually starts as a muscle hematoma following trauma. It commonly presents as a slow growing, painless cystic mass with variable clinical and radiological features depending on its anatomical location. An osseous pseudotumor mainly occurs in adults and commonly involves the femur, pelvis, tibia and short bones in a descending order of incidence.45 Soft tissue pseudotumor commonly occurs in muscles (iliopsoas, quadriceps, triceps surae and gluteus muscle).4 Intraabdominal or pelvic hematoma is usually not diagnosed early due to the absence of external signs. It often grows over many years to a large size and causes pressure effect on adjacent vital organs as seen in our patient. This should be recognized early and adequately treated with factor replacement to prevent late sequelae. Massive intraabdominal pseudotumors are associated with fatal complications like septicemia due to erosion into the bowel or cyst infection.6 Surgical excision of the pseudotumor is the most effective and curative in most patients.7 With the easy availability of clotting factor preparations, surgical removal of pseudotumors has become the standard modality of treatment. Recurrence rate after surgical excision is 15%.6 Hemophilic pseudotumor very rarely affects vertebral column and is not reported in literature.

The artery of Adamkiewicz is the largest medullary artery feeding the anterior spinal artery at the lower thoracic region. It is present on the left side in 80% of individuals. It is usually located from T7 to T11. It is uncommon at L1 vertebral level. The reported incidence of neurological deficit (paraplegia) following thoracolumbar aneurysm repair and ligation of segmental arteries is 12.5- 16%.8

We have presented a case with hemophilic pseudotumor involving the first lumbar vertebra and the left iliopsoas muscle, managed by surgical excision. We also report the incidental, uncommon yet critical location of the artery of Adamkiewicz. The psoas muscle pseudotumor was excised through the retroperitoneal approach in our case. In long standing cases; the pseudotumor is firmly attached to adjacent vital structures. This can complicate the surgical procedure. We had a laceration of the left common iliac vessels, which was dealt with satisfactorily. The lumbosacral plexus was also firmly attached to the pseudotumor wall. Though the excision of L1 vertebra was needed for complete pseudotumor removal, it was avoided to prevent damage to the artery of Adamkiewicz. Liu et al.9 in their study have reported a case with lumbar epidural pseudotumor showing scalloping of adjacent bony canal. Though anomalous origin of artery of Adamkiewicz is an incidental finding, it influenced the extent of surgical resection in our case. With the wide availability and utilization of factor VIII and activated prothrombin complex concentrate, surgical excision of pseudotumor can be performed safely. One however needs to be cautious since intraoperative rupture of the hemophilic tumor may adversely complicate the operative procedure.