Clinical and Radiologic Analysis of Posterior Apophyseal Ring Separation Associated with Lumbar Disc Herniation

OBJECTIVE: We analyzed the clinical and radiologic features of posterior apophyseal ring separation (PARS) with lumbar disc herniation and suggest the proper management options according to the PARS characteristics. METHODS: We reviewed case series of patients with PARS who underwent surgery of lumbar disc herniation. Preoperative symptoms, neurologic status, Body Mass Index, preoperative and postoperative Visual Analogue Scale (VAS) and Korean-Oswestry Disability Index (K-ODI) scores, operation types were obtained. PARS size, locations, the degree of resection were assessed. RESULTS: PARS was diagnosed in 109 (7.5%) patients among 1448 patients given surgical treatment for single level lumbar disc herniation. There were 55 (50.5%) small PARS and 54 (49.5%) large PARS. Among the large PARS group, 15 (27.8%) had lower endplate PARS of upper vertebra at the level of disc herniation. Thirty-nine (72.2%) were upper endplate PARS of lower vertebra. Among the group with upper endplate PARS of lower vertebra, unresected PARS was diagnosed in 12 (30.8%) cases and resected PARS was diagnosed in 27 (69.2%) cases. VAS and K-ODI scores changes were 3.6+/-2.9 and 5.4+/-6.4 in the unresected PARS group, 5.8+/-2.1 and 11.3+/-7.1 in the resected PARS group. The group with upper endplate PARS of lower vertebra showed significant difference of VAS (p=0.01) and K-ODI (p=0.013) score changes between unresected and resected PARS groups. CONCLUSION: The large PARS of upper endplate in lower vertebra should be removed during the surgery of lumbar disc herniation. High level or bilateral side of PARS should be widely decompressed and arthrodesis procedures are necessary if there is a possibility of secondary instability.

V-Rod Technique for Direct Repair Surgery of Pediatric Lumbar Spondylolysis Combined with Posterior Apophyseal Ring Fracture

We report a pediatric baseball player having both a fracture of the posterior ring apophysis and spondylolysis. He was presented to a primary care physician complaining of back pain and leg pain. Despite conservative treatment for 3 months, the pain did not subside. He was referred to our clinic, and surgical intervention was carried out. First, a bony fragment of the caudal L5 apophyseal ring was removed following fenestration at the L5-S interlaminal space, bilaterally: and decompression of the bilateral S1 nerve roots was confirmed. Next, pseudoarthrosis of the L5 pars was refreshed and pedicle screws were inserted bilaterally. A v-shaped rod was inserted beneath the L5 spinous process, which stabilized the pars defects. After the surgery, back pain and leg pain completely disappeared. In conclusion, the v-rod technique is appropriate for the spondylolysis direct repair surgery, especially, in case the loose lamina would have a partial laminotomy.

Clinical Analysis of Posterior Lymbar Apophyseal Ring Fractures in Young Adults

Lumbar apophyseal ring fracture occurs between the vertebral ring apophyses and the cartilaginous rim of the superior or inferior margins of the vertebral end plates. This fracture is an unusual disease that if typically seen in adolescents or young adults. We analyzed the clinical records and neuroradiologic imagings of 49 patients who were less than 29 years old diagnosed with posterior lumbar apophyseal ring fractures in regards to the age, trauma history, the type and distribution of the fracture, clinical presentation, and postoperative outcome. The posterior lumbar apophseal ring fractures were detected in 29(9.2%) out of 533 young adult patients with herniated lumbar discs. There was trauma history in 37(75.5%) out of the 49 patients. The main presenting symptoms in most of the patients were low back pain and radiating leg pain. In patients who presented with symptoms, thirty-five patients(75.5%) had a positive straight leg-raising test. According to classification by Takata, they were type I in 12 cas es(24.0%), type II in 9 cases(18.0%), and type III in 29 cases(58.0%). The type III with trauma history was more common than with non-trauma history(p<0.01). Twenty-one patients(42.0%) had bony fragments projecting into the spinal canal from the upper border of S1. Partial hemilaminectomy(18 patients) and total laminectomy(3 patients) were performed. We could easily remove the bony fragments in all of the surgical cases. Chemonucleolysis were done in three patients. The overall results were good. We conclude that knowledge of this entity and correct radiographic diagnosis will help to facilitate the operative planning.