Our study shows that single-stage transverse process resection, debridement, interbody fusion and pedicle screw fixation via posterior-only approach is an effective and feasible approach for the treatment of lumbar spinal TB with kyphosis deformity and neurological deficits. However, standard anti-TB therapy, strict bed rest, and supportive therapy remain the fundamental approaches for treating spinal TB. Surgical intervention is only recommended for lumbar spinal TB patients with abscess formation, spinal cord compression, significant kyphosis deformity, and neurological dysfunction.
Spinal TB accounts for almost half of the bone and joint TB, mainly affecting the anterior and middle column of the spine and leading to vertebral bone defects, collapse, compression, and kyphosis deformity [17]. The anterior-only approach is preferred for decompression and debridement in spinal TB as it allows direct access to the lesion site, complete debridement, sufficient decompression, and reduces muscle trauma [18]. However, the high frequency of complications such as pseudarthrosis, ineffective correction of kyphosis and maintenance of the correction, unsatisfactory neurological function, and vascular injuries overwhelm its advantages [19]. Many researchers reported that patients treated by the anterior-only approach experience more significant blood loss, longer duration of the operation, and the hospitalization period than that of the posterior-only approach [20]. Combined anterior and posterior surgery has become popular due to its beneficial clinical outcomes [21]. However, when poor conditions complicate the aged, it would be difficult to tide over the serious trauma such as more significant loss of blood, longer operation time, and approach-related complications [22]. Furthermore, no literature reports in the surgical management of lumbar spinal TB by single-stage transverse process resection, debridement, interbody fusion, and internal fixation via a posterior-only approach.
Controversies on the strategy of a posterior-only approach in treating lumbar spinal TB mainly concentrated in whether surgeons can throughly perform debridement and anterior decompression in such a limited visual field, whether it would achieve the anterior bony fusion, and whether it would maintain the spinal stability [23, 24]. A number of advantages to the posterior-only approach were highlighted: reduced bleeding, shorter operation and hospitalization durations, released the nerve compression, corrected kyphosis deformity, regained spinal stability, and improved the quality of life of these patients [25]. These results reflect those of Abulizi et al. who also found that single-stage transforaminal decompression, debridement, interbody fusion, and posterior instrumentation is an effective and safe surgical for the treatment of spinal infection [14]. Additionally, as far as the patients with less involved spinal TB for the anterior column that is mainly affected by TB achieving spontaneous fusion are concerned, the posterior-only approach may be a better strategy [26, 27].
Although previous studies have demonstrated that the translaminar debridement and transforaminal bone graft are feasible with minimal damage to the posterior column, the operation still results in a certain degree of damage to the lamina or the superior and inferior articular processes [28]. Therefore, some investigators have several concerns: (1) if the lesion of spinal TB involves the anterior and middle column, surgery via posterior approach may cause the metastasis of lesion into the posterior column, even retrograde infection caused by spinal dura rupture; (2) the structure destruction of the lamina and articular processes by the posterior surgery results in the disruption of the three-column spine may aggravate the instability of the diseased vertebrae. In this study, the authors began to explore whether the debridement, intervertebral bone grafting, internal fixation, and reconstruction of spinal stability can be achieved without destroying the lamina and the superior and inferior articular processes.
The single-stage posterior approach proposed by the authors is based on posterior en-bloc resection of spinal tumor and oblique lumbar interbody fusion (OLIF) technique. The feasibility of this approach need to be highlighted: (1) the surgery access is constructed by posterior en-bloc block resection to remove the transverse processes of the superior vertebral body and a small part of the lamina above the intervertebral foramen to expose the nerve root of the involved segment. This strategy not only meets the requirement of not destroying the lamina structure and superior and inferior articular processes but also achieve the debridement; (2) the operation area is mainly in the posterolateral lumbar spine. The long-segment bone graft from posterior to anterior with intervertebral foramen decompression and transforaminal lumbar interbody fusion (TLIF) cannot be achieved [29]. Additionally, this method of long-segment bone graft with interlaminar decompression and posterior lumbar interbody fusion (PLIF) approach is infeasible [30]. Therefore, OLIF fusion technique can only be used for interbody fusion. According to these two ideas, the problems of lesion debridement, bone grafting in the anterior and middle column can be treated poster laterally. Combine the absolute advantages of posterior internal fixation and correction of the deformity, we believe that this surgical approach can be used as a surgical choice for lumbar spinal TB.
This study holds several limitations. The potential risk of TB spreading to the healthy posterior regions is concerned in this surgical therapy, as posterior debridement can result in diffusion of infection and fistulas. Fortunately, this complication was not found in our research. Our study included 32 patients, future study should include multicentre studies and larger sample size to confirm our results. Furthermore, some patients with missing data or lost to follow-up were excluded from the analysis. The future management of these patients should be enhanced with further long-term follow-up data to closely monitor the effect of this surgical option.