HAMSTRING TIGHTNESS AND SCIATICA IN YOUNG PATIENTS WITH DISC HERNIATION

Transcription

1 HAMSTRNG TGHTNESS AND SATA N YOUNG PATENTS WTH DS HERNATON KEH TAKATA, KAZUHSA TAKAHASH From hiba University, hiba, Japan We evaluated the nerve roots of the cauda equina by T myelography in 36 patients aged from 11 to 19 years with lumbar disc herniation. On straightlegraising tests, six younger patients had isolated hamstring tightness with no sciatica (group A) and 30 had sciatic pain (group B). T myelography showed that no patient in group A had associated nerveroot swelling, and that the roots were displaced posteriorly, but not compressed. n 21 of the groupb patients, swelling of the nerve roots was confirmed, with compression between the herniated disc and the superior articular process. Our findings suggest that hamstring tightness in these patients may be caused by a different mechanism from that which causes sciatic pain. J BoneJoint Surg [Br] 1994; 76B:2204. operation for posterior discectomy. Their ages ranged from 11 to 19 years, and the disc herniation was at L4L5 in 17 and L5S1 in 19 (Table ). Six of the patients, group A, had isolated hamstring tightness with no sciatic pain on straightleg raising. The other 30, group B, had sciatic pain on straightleg raising. Patients with hamstring tightness and sciatica occurring simultaneously were included in group B. All 36 patients had T myelograms performed by one of the authors (K. Takata), obtaining six or seven slices for each vertebral level, each of 5 mm thickness. Reconstructions of both osseous and softtissue structures were performed, with computer visualisation of the nerve roots within the dural tube filled with contrast medium. Softtissue imaging was used to delineate the nerve roots outside the dural tube. Received 14 May 1993; Accepted after revision 28 September 1993 RESULTS Young patients with lumbar disc herniation sometimes show hamstring tightness on straightleg raising with no associated sciatic pain. The pathogenesis of hamstring tightness in such cases is uncertain, although we have shown a close relationship between the severity of sciatica and nerveroot swelling as revealed by T myelography (Takata et al 1988a). We used this radiographic method to study the nerve roots of the cauda equina of 36 patients aged from 1 1 to 19 years with lumbar disc herniation to investigate the aetiology of hamstring tightness. PATENTS AND METhODS T myelography was performed on 27 males and nine females with lumbar disc herniation, later confirmed at K. Takata, MD, onsultant Orthopaedic Surgeon K. Takahashi, MD, Assistant Professor of Orthopaedic Surgery Department of Orthopaedic Surgery, hiba University School of Medicine, 181 nohana, huouku, hiba 260, Japan. orrespondence should be sent to Dr K. Takahashi British Editorial Society of Bone and Joint Surgery X/94/2757 $2.00 Details of the patients are shown in Table. The patients with hamstring tightness alone (group A) were aged 11 (3), 12 (2) and 14 years (1). Older patients predominated in group B. n group A, four herniations were at the L5S1 level and two at L4L5. Neurological examination in these patients showed no abnormalities of deep tendon reflexes, sensation, or muscle strength. All groupb patients had some neurological deficits. Five of the six groupa patients had bilateral restriction of straightleg raising; only seven of the 30 groupb patients had bilateral involvement. T showed central herniation in five ofthe six group A patients, and posterolateral herniation in 18 of the 30 groupb patients. All groupa patients had a fracture of the posterior margin of the adjacent lumbar vertebral body (Takata et al 1988b), by simple separation of the entire margin, which appeared as an arcuate structure in the spinal canal (type of Takata et al 1988b). Posterior margin fractures were seen in only 15 of the 30 patients in group B. T myelography revealed swollen nerve roots in 21 of group B, and in none of group A. n groupb patients, the involved nerve roots were shown to be compressed between the herniated mass and the superior articular process. n groupa patients, the involved nerve roots were displaced posteriorly without being compressed. 220 THE JOURNAL OF BONE AND JONT SURGERY

2 HAMSTRNG TGHTNESS AND SATA N YOUNG PATENTS WTH DS HERNATON 221 Table. Details of 36 young patients with lumbar disc herniation. Group A (hamstring tightness only) had no neurological deficit and no T evidence of nerveroot compression (see text) Age Group ase (yr) Sex Level SLR* Site of protrusiont Marginal fractures Nerveroot swelling A 1 11 F L4L M lisi 3 11 M lisi 4 12 M L4L M L5Sl 6 14 M L55l HT(LR) HT(LR) HT(LR) HT(LR) HT(LR) HT(L) B 7 12 M L5Sl 8 12 F L55l 9 13 F L4L M L5Sl M lisi M lisi F L4L F L4L F L4L F L5Sl M L4L M L4L F L5Sl M L4L M L4L M L4L M L4L M L5Sl M [ M L4L M L4L M L5S M lisi M L5S F L5S M L4L M L4L M L4L M L5Sl M L5S1 45(R) 45 (R) 45 (L) 30 (L) 15(R) 5(R)5(L) 10(R) lo(r)10(l) 10(L) 45 (R) 45 (L) 40(R)40(L) 45(L) 45(L) 15(L) 40(R) 5(L) ll ll #{247} #{247} t straightleg raising (degrees) t, central;, posterolateral :1: classification, see Takata et at ( 1988b) HT, isolated hamstring tightness; L c ftsided; R, rightsided llustrative cases ase 2. An 1 1yearold boy had a twomonth history of severe hamstring tightness with straightleg raising limited to approximately 5#{176} bilaterally. He walked on his toes with his knees flexed, but did not complain of sciatic pain, and there was no evidence of muscle weakness or sensory deficit. T myelography showed a lumbar disc herniation at L5S1 with an associated marginal fracture ofthe vertebral body (Figs 1 and 2; type, Takata et al 1988b). The nerve roots were located in the wide lateral recesses, and were neither compressed nor swollen. After a posterior discectomy, there was gradual relief of the hamstring tightness over a sixmonth period. n other groupa patients, it took three to six months for complete relief of hamstring tightness, contrasting with the relatively rapid relief of sciatic pain in groupb patients. ase 35. A 19yearold man had typical rightsided sciatica, with severe pain at 20#{176} straightleg raising. nvestigations showed that a swollen right 51 nerve root was compressed between the herniated mass and the superior articular process (Figs 3 and 4). DSUSSON Severe restriction of straightleg raising has been described as characteristic of lumbar disc herniation in teenage patients (B#{248}rgesen and Vang 1974), but it is not clear whether this is due to a different mechanism from that in adults (Rugtveit 1966; Nelson et al 1972). The differing reports may be because of lack of discrimination between sciatic pain and hamstring tightness, both of which are often present to some extent. We attempted to define two different groups. We have previously reported the relation between nerveroot swelling and the severity of sciatica, showing that inflammation in a nerve root may have a role in causing sciatic pain (Takata et al 1988a). We have also shown that some young patients had severe restriction of straightleg raising without nerveroot swelling, and that this restriction was due to tightness of the hamstrings. The patients with hamstring tightness and no sciatica all had wide lateral recesses in the lumbar spinal canal, which is probably normal for this age group. The nerve roots were shifted posteriorly, but not compressed between the herniated disc with its arcuate osseous fragment and VOL. 76B, No. 2, MARH 1994

3 222 K. TAKATA, K. TAKAHASH Fig. 1 ase 2. Figure 1 Myelograms of an 1 1 yearold boy with a twomonth history of bilateral hamstring tightness. A) Lateral myelogram showing an anterior indentation. B) Anteroposterior myelogram showing contrast medium in the root sheath of both first sacral nerve roots (arrows), indicating the absence of compression in the lateral recesses. Figure 2 A) A F myelogram of the bony tissues at the middle of L5 shows no swelling of the first sacral nerve roots (arrows). B) and ) T myelograms of the soft tissues show a herniated lumbar disc accompanied by an arcuate bony fragment. The first sacral nerve roots are not compressed but have been shifted posteriorly into wide lateral recesses. Scan B is at the L5S1 intervertebral disc level; scan is at the upper margin of Si. Fig. 2 THE JOURNAL OF BONE AND JONT SURGERY

4 HAMSTRNG TGHTNESS AND SATA N YOUNG PATENTS WTH DS HERNATON 223 Fig. 3 ase 35. Figure 3 Myelograms of a 19yearold man with a disc herniation at L5S1 causing severe rightsided sciatica. A) Rightoblique myelogram shows a filling defect in the root sheath of the 51 root, caused by compression in the lateral recess. B) Leftoblique myelogram shows normal filling of the left root sheath. Figure 4 A) and B) cr myelograms of the bony tissues show swelling of the right S 1 root (arrows). Scan A is at the middle of i vertebra; scan B is of the lower quarter of L5 vertebra. ) T myelogram of soft tissues at the L5S1 disc level, showing a central herniation with compression of the right Si root (arrow) between the herniated mass and the superior facet. Fig. 4 VOL 76B, No. 2, MARH 1994

5 224 K. TAKATA, K TAKAHASH the Superior articular process. We found no morphological changes in the nerve roots and no neurological deficits in this group. t appears that isolated hamstring tightness without sciatic pain is seen only in patients with a lumbar disc herniation including an arcuate fragment and with wide lateral recesses. Sprangfort (1971) reported that the incidence of restricted straightleg raising decreases with age, and postulated increased tension on the neural tissues in children. Specific hamstring tightness may be related to the stretching of elements of the cauda equina during the rapid growth period in children. Our study also showed that nerveroot compression rather than stretching is the cause of sciatica. ompression in addition to stretching may produce sciatica and hamstring tightness simultaneously, and this mixed presentation is commonly seen in teenage patients. solated hamstring tightness did not appear to be caused by the same pathogenic mechanism as sciatica, and investigation should discriminate between the two sets of symptoms. No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. REFERENES B#{248}rgesenSE, yang PS. Herniation of the lumbar intervertebral disk in children and adolescents. Acta Orthop Scand 1974; 45:5409. Nelson L, Janecki J, Gildenberg, Sava G. Disk protrusions in the young. lin Orthop 1972; 88: Rugtveit A. Juvenile lumbar disc herniations. Acta Orthop Scand 1966; 37: Spraagfort E. Las#{232}gue s sign in patients with lumbar disc herniation. Acta Orthop ScaM 1971; 42: Takata K, aoue S, Takahashi K, Ohtsuka Y. Swelling of the cauda equina in patients who have herniation of a lumbar disc: a possible pathogenesis of sciatica. J Bonefoint Surg [Am] 1988a; 70A:3618. Takata K, aoue S, Takahashi K, Ohtsuka Y. Fracture of the posterior margin of a lumbar vertebral body. J Bone Joint Surg [Am] 1988b; 70A: THE JOURNAL OF BONE AND JONT SURGERY