Elias Dakwar, Amir Ahmadian and Juan S. Uribe
The thoracolumbar junction (T11–L2) poses an anatomical dilemma, given the presence of the lower rib cage and the diaphragm when performing anterolateral approaches. To circumvent dealing with the diaphragm, a minimally invasive lateral extracoelomic approach has been used to approach the thoracolumbar junction by mobilizing the diaphragm anteriorly. No anatomical studies have described the attachments of the diaphragm and their surgical significance during the lateral approach to the thoracolumbar spine. The objective of this study is to describe the anatomical relationship of the diaphragm in reference to the minimally invasive lateral approach to the thoracolumbar spine and its surgical significance.
Nine adult fresh-frozen cadaveric specimens were dissected and studied (18 sides). All specimens were placed in the lateral decubitus position, similar to the surgical technique, for the dissections. The relationship between the retroperitoneum, retropleural space, diaphragm, and thoracolumbar spine was analyzed in reference to the minimally invasive lateral approach. Special attention was given to the attachments of the diaphragm and their relationship to the ribs during the early stages of the approach.
All 18 sides were successfully dissected, analyzed, and photographed. The diaphragm is a musculotendinous sheet extending between the thoracic and abdominal cavities. Its attachments can be divided into 3 main categories: 1) sternal or anterior, 2) costal or lateral, and 3) lumbar or posterior. These attachments are described in detail, with specific reference to the lateral approach. When performing the minimally invasive lateral extracoelomic approach to the thoracolumbar spine, the lateral and posterior attachments must be identified and dissected to successfully mobilize the diaphragm anteriorly.
The diaphragm has multiple attachments that can be categorized as anterior, lateral, and posterior. In reference to the minimally invasive lateral extracoelomic approach to the thoracolumbar junction, the surgically significant attachments are primarily to the 12th rib and transverse process of L-1.
Amir Ahmadian, Armen R. Deukmedjian, Naomi Abel, Elias Dakwar and Juan S. Uribe
The minimally invasive lateral transpsoas approach has become an increasingly popular means of fusion. The most frequent complication is related to lumbar plexus nerve injuries; these can be diagnosed based on distribution of neurological deficit following the motor and/or sensory nerve injury. However, the literature has failed to provide a clinically relevant description of these complications. With accurate clinical diagnosis, spine practitioners can provide more precise prognostic and management recommendations to include observation, nerve blocks, neurodestructive procedures, medications, or surgical repair strategies. The purpose of this study was to standardize the clinical findings of lumbar plexopathies and nerve injuries associated with minimally invasive lateral retroperitoneal transpsoas lumbar fusion.
A thorough literature search of the MEDLINE database up to June 2012 was performed to identify studies that reported lumbar plexus and nerve injuries after the minimally invasive lateral retroperitoneal transpsoas approach. Included studies were assessed for described neurological deficits postoperatively. Studies that did attempt to describe nerve-related complications clinically were excluded. A clinically relevant assessment of lumbar plexus nerve injury was derived to standardize early diagnosis and outline prognostic implications.
A total of 18 studies were selected with a total of 2310 patients; 304 patients were reported to have possible plexus-related complications. The incidence of documented nerve and/or root injury and abdominal paresis ranged from 0% to 3.4% and 4.2%, respectively. Motor weakness ranged from 0.7% to 33.6%. Sensory complications ranged from 0% to 75%. A lack of consistency in the descriptions of the lumbar plexopathies and/or nerve injuries as well as a lack of diagnostic paradigms was noted across studies reviewed. Sensory dermal zones were established and a standardized approach was proposed.
There is underreporting of postoperative lumbar plexus nerve injury and a lack of standardization of clinical findings of neural complications related to the minimally invasive lateral retroperitoneal transpsoas approach. The authors provide a diagnostic paradigm that allows for an efficient and accurate classification of postoperative lumbar plexopathies and nerve injuries.
Phoenix, Arizona • March 6–9, 2013