The Role of the Ligamentum Flavum Area as a Morphological Parameter of Lumbar Central Spinal Stenosis.

BACKGROUND: Hypertrophy of the ligamentum flavum (LF) has been considered as a major cause of lumbar central spinal stenosis (LCSS). Previous studies have found that ligamentum flavum thickness (LFT) is correlated with aging, disc degeneration, and lumbar spinal stenosis. However, hypertrophy is different from thickness. Thus, to evaluate hypertrophy of the whole LF, we devised a new morphological parameter, called the ligamentum flavum area (LFA). OBJECTIVES: We hypothesized that the LFA is a key morphologic parameter in the diagnosis of LCSS. STUDY DESIGN: Retrospective observational study. SETTING: The single center study in Seoul, Republic of Korea. METHODS: LF samples were collected from 166 patients with LCSS, and from 167 controls who underwent lumbar magnetic resonance imaging (MRI) as part of a routine medical examination. T1-weighted axial MR imageswere acquired at the facet joint level from individual patients. We measured the LFA and LFT at the L4-L5 intervertebral level on MRI using a picture archiving and communications system. The LFA was measured as the cross-sectional area of the whole LF at the L4-L5 stenotic level. The LFT was measured by drawing a line along the side of the ligament facing the spinal canal and along the laminar side of the ligament curve and then measuring the thickest point at the L4-L5 level. RESULTS: The average LFA was 96.56 ± 30.74 mm2 in the control group and 132.69 ± 32.68 mm2 in the LCSS group. The average LFT was 3.61 ± 0.72 mm in the control group and 4.24 ± 0.97 mm in the LCSS group. LCSS patients had significantly higher LFA (P < 0.001) and LFT (P < 0.001). Regarding the validity of both LFA and LFT as predictors of LCSS, Receiver Operator Characteristics (ROC) curve analysis showed that the best cut-off point for the LFA was 105.90 mm2, with 80.1% sensitivity, 76.0% specificity, and area under the curve (AUC) of 0.83 (95% CI, 0.78 - 0.87). The best cut off-point of the LFT was 3.74 mm, with 70.5% sensitivity, 66.5% specificity, and AUC of 0.72 (95% CI, 0.66 - 0.77). LIMITATIONS: The principal methodological limitation was the retrospective observational nature. Anatomically, degenerative lumbar spinal stenosis can involve the central canal, foramina, and lateral recess. However, we focused on LCSS only. CONCLUSIONS: Although the LFT and LFA were both significantly associated with LCSS, the LFA was a more sensitive measurement parameter. Thus, to evaluate LCSS patients, the treating doctor should more carefully analyze the LFA than LFT.Institutional Review Board (IRB) approval number: S2015-1328-0001Key words: Ligamentum flavum, ligamentum flavum area, ligamentum flavum thickness, lumbar central spinal stenosis, hypertrophy of the ligamentum flavum, morphological parameter, cross-sectional area, optimal cut-off point.

A brief report on a technical description of ultrasound-guided lumbar sympathetic block.

The lumbar sympathetic ganglion block (LSGB) is widely used for diagnosing and treating sympathetically maintained pain disorders. The LSGB has been conventionally carried out under fluoroscopy or computed tomography guidance. However, as ultrasound technology improved, ultrasound-guided interventions have been expanding their territory to deeper structures. Ultrasound guidance provides many benefits including protecting vascular injection, shortening procedure time in some cases, and reducing the emission of radiation. In this report, we describe a successful case of a US-guided LSGB without major complications. We expect that US-guided LSGBs can be implemented and furnished in the daily outpatient clinical setting by highly trained pain physicians.

The effect of polydeoxyribonucleotide prolotherapy on posterior tibial tendon dysfunction after ankle syndesmotic surgery: A case report.

RATIONALE: Ankle syndesmotic injuries occasionally require long-term therapy for recovery and can result in tendon injury. Posterior tibial tendon dysfunction (PTTD) is an acquired deformity that can cause flatfoot deformity. The current nonoperative management of PTTD includes nonsteroidal antiinflammatory drugs (NSAIDs), orthopedic devices. Although various treatment options have been attempted, optimal treatments for each stage of the condition are debated. Polydeoxyribonucleotide (PDRN) is effective in healing of chronic wounds associated with tissue damage by attracting tissue growth factors. PATIENT CONCERNS: A 67-year-old woman who presented at our pain clinic with pain on the inside of ankle. She had a syndesmotic screw fixation 3 years prior. Her ankle pain had persisted after the removal of screws and edema for about 1 month resulting from long-term NSAIDs administration. DIAGNOSES: The origin of the pain was possibly tibialis posterior muscle and posterior tibial tendon and she was diagnosed as PTTD after syndesmosis surgery. INTERVENTIONS: Sono guided prolotherapy with PDRN was carried out. OUTCOMES: Patient showed improvement in the arch of the foot, experienced pain relief, and was able to wear regular shoes without any orthopedic device. LESSONS: This case report highlights that PDRN prolotherapy is a safe and efficient therapeutic option for the treatment of PTTD.